Bump pip from 21.0.1 to 21.1 (PR #2884)

Bumps [pip](https://github.com/pypa/pip) from 21.0.1 to 21.1.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/pypa/pip/blob/main/NEWS.rst">pip's changelog</a>.</em></p>
<blockquote>
<h1>21.1 (2021-04-24)</h1>
<h2>Process</h2>
<ul>
<li>Start installation scheme migration from <code>distutils</code> to <code>sysconfig</code>. A
warning is implemented to detect differences between the two implementations to
encourage user reports, so we can avoid breakages before they happen.</li>
</ul>
<h2>Features</h2>
<ul>
<li>Add the ability for the new resolver to process URL constraints. (<code>[#8253](pypa/pip#8253) &lt;https://github.com/pypa/pip/issues/8253&gt;</code>_)</li>
<li>Add a feature <code>--use-feature=in-tree-build</code> to build local projects in-place
when installing. This is expected to become the default behavior in pip 21.3;
see <code>Installing from local packages &lt;https://pip.pypa.io/en/stable/user_guide/#installing-from-local-packages&gt;</code>_
for more information. (<code>[#9091](pypa/pip#9091) &lt;https://github.com/pypa/pip/issues/9091&gt;</code>_)</li>
<li>Bring back the &quot;(from versions: ...)&quot; message, that was shown on resolution failures. (<code>[#9139](pypa/pip#9139) &lt;https://github.com/pypa/pip/issues/9139&gt;</code>_)</li>
<li>Add support for editable installs for project with only setup.cfg files. (<code>[#9547](pypa/pip#9547) &lt;https://github.com/pypa/pip/issues/9547&gt;</code>_)</li>
<li>Improve performance when picking the best file from indexes during <code>pip install</code>. (<code>[#9748](pypa/pip#9748) &lt;https://github.com/pypa/pip/issues/9748&gt;</code>_)</li>
<li>Warn instead of erroring out when doing a PEP 517 build in presence of
<code>--build-option</code>. Warn when doing a PEP 517 build in presence of
<code>--global-option</code>. (<code>[#9774](pypa/pip#9774) &lt;https://github.com/pypa/pip/issues/9774&gt;</code>_)</li>
</ul>
<h2>Bug Fixes</h2>
<ul>
<li>Fixed <code>--target</code> to work with <code>--editable</code> installs. (<code>[#4390](pypa/pip#4390) &lt;https://github.com/pypa/pip/issues/4390&gt;</code>_)</li>
<li>Add a warning, discouraging the usage of pip as root, outside a virtual environment. (<code>[#6409](pypa/pip#6409) &lt;https://github.com/pypa/pip/issues/6409&gt;</code>_)</li>
<li>Ignore <code>.dist-info</code> directories if the stem is not a valid Python distribution
name, so they don't show up in e.g. <code>pip freeze</code>. (<code>[#7269](pypa/pip#7269) &lt;https://github.com/pypa/pip/issues/7269&gt;</code>_)</li>
<li>Only query the keyring for URLs that actually trigger error 401.
This prevents an unnecessary keyring unlock prompt on every pip install
invocation (even with default index URL which is not password protected). (<code>[#8090](pypa/pip#8090) &lt;https://github.com/pypa/pip/issues/8090&gt;</code>_)</li>
<li>Prevent packages already-installed alongside with pip to be injected into an
isolated build environment during build-time dependency population. (<code>[#8214](pypa/pip#8214) &lt;https://github.com/pypa/pip/issues/8214&gt;</code>_)</li>
<li>Fix <code>pip freeze</code> permission denied error in order to display an understandable error message and offer solutions. (<code>[#8418](pypa/pip#8418) &lt;https://github.com/pypa/pip/issues/8418&gt;</code>_)</li>
<li>Correctly uninstall script files (from setuptools' <code>scripts</code> argument), when installed with <code>--user</code>. (<code>[#8733](pypa/pip#8733) &lt;https://github.com/pypa/pip/issues/8733&gt;</code>_)</li>
<li>New resolver: When a requirement is requested both via a direct URL
(<code>req @ URL</code>) and via version specifier with extras (<code>req[extra]</code>), the
resolver will now be able to use the URL to correctly resolve the requirement
with extras. (<code>[#8785](pypa/pip#8785) &lt;https://github.com/pypa/pip/issues/8785&gt;</code>_)</li>
<li>New resolver: Show relevant entries from user-supplied constraint files in the
error message to improve debuggability. (<code>[#9300](pypa/pip#9300) &lt;https://github.com/pypa/pip/issues/9300&gt;</code>_)</li>
<li>Avoid parsing version to make the version check more robust against lousily
debundled downstream distributions. (<code>[#9348](pypa/pip#9348) &lt;https://github.com/pypa/pip/issues/9348&gt;</code>_)</li>
<li><code>--user</code> is no longer suggested incorrectly when pip fails with a permission
error in a virtual environment. (<code>[#9409](pypa/pip#9409) &lt;https://github.com/pypa/pip/issues/9409&gt;</code>_)</li>
<li>Fix incorrect reporting on <code>Requires-Python</code> conflicts. (<code>[#9541](pypa/pip#9541) &lt;https://github.com/pypa/pip/issues/9541&gt;</code>_)</li>
</ul>
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</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/pypa/pip/commit/2b2a268d25963727c2a1c805de8f0246b9cd63f6"><code>2b2a268</code></a> Bump for release</li>
<li><a href="https://github.com/pypa/pip/commit/ea761a6575f37b90cf89035ee8be3808cf872184"><code>ea761a6</code></a> Update AUTHORS.txt</li>
<li><a href="https://github.com/pypa/pip/commit/2edd3fdf2af2f09dce5085ef0eb54684b4f9bc04"><code>2edd3fd</code></a> Postpone a deprecation to 21.2</li>
<li><a href="https://github.com/pypa/pip/commit/3cccfbf169bd35133ee25d2543659b9c1e262f8c"><code>3cccfbf</code></a> Rename mislabeled news fragment</li>
<li><a href="https://github.com/pypa/pip/commit/21cd124b5d40b510295c201b9152a65ac3337a37"><code>21cd124</code></a> Fix NEWS.rst placeholder position</li>
<li><a href="https://github.com/pypa/pip/commit/e46bdda9711392fec0c45c1175bae6db847cb30b"><code>e46bdda</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pypa/pip/issues/9827">#9827</a> from pradyunsg/fix-git-improper-tag-handling</li>
<li><a href="https://github.com/pypa/pip/commit/0e4938d269815a5bf1dd8c16e851cb1199fc5317"><code>0e4938d</code></a> 📰</li>
<li><a href="https://github.com/pypa/pip/commit/ca832b2836e0bffa7cf95589acdcd71230f5834e"><code>ca832b2</code></a> Don't split git references on unicode separators</li>
<li><a href="https://github.com/pypa/pip/commit/1320bac4ff80d76b8fba2c8b4b4614a40fb9c6c3"><code>1320bac</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pypa/pip/issues/9814">#9814</a> from pradyunsg/revamp-ci-apr-2021-v2</li>
<li><a href="https://github.com/pypa/pip/commit/e9cc23ffd97cb6d66d32dc3ec27cf832524bb33d"><code>e9cc23f</code></a> Skip checks on PRs only</li>
<li>Additional commits viewable in <a href="https://github.com/pypa/pip/compare/21.0.1...21.1">compare view</a></li>
</ul>
</details>
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changelogs/unreleased/2884-dependabot.yml

@@ -0,0 +1,5 @@
+change-type: patch
+description: Bump pip from 21.0.1 to 21.1
+destination-branches:
+- master
+sections: {}

requirements.txt

@@ -12,7 +12,7 @@ jinja2==2.11.3
 more-itertools==8.7.0
 netifaces==0.10.9
 packaging==20.9
-pip==21.0.1
+pip==21.1
 ply==3.11
 pydantic==1.8.1
 pyformance==0.4