Bump virtualenv from 20.7.2 to 20.8.1 in /.github/workflows (#44)

Bumps [virtualenv](https://github.com/pypa/virtualenv) from 20.7.2 to 20.8.1.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst">virtualenv's changelog</a>.</em></p>
<blockquote>
<h2>v20.8.1 (2021-09-24)</h2>
<p>Bugfixes - 20.8.1</p>
<pre><code>- Fixed a bug where while creating a venv on top of an existing one, without cleaning, when seeded
  wheel version mismatch occurred, multiple ``.dist-info`` directories may be present, confounding entrypoint
  discovery - by :user:`arcivanov` (`[#2185](pypa/virtualenv#2185) &lt;https://github.com/pypa/virtualenv/issues/2185&gt;`_)
- Bump embed setuptools from ``58.0.4`` to ``58.1.0`` - by :user:`gaborbernat`. (`[#2195](pypa/virtualenv#2195) &lt;https://github.com/pypa/virtualenv/issues/2195&gt;`_)
<p>Misc - 20.8.1</p>
<pre><code>- `[#2189](pypa/virtualenv#2189) &amp;lt;https://github.com/pypa/virtualenv/issues/2189&amp;gt;`_


v20.8.0 (2021-09-16)
--------------------

* upgrade embedded setuptools to ``58.0.4`` from ``57.4.0`` and pip to ``21.2.4`` from ``21.2.3``
* Add nushell activation script
&lt;/code&gt;&lt;/pre&gt;
&lt;/blockquote&gt;
&lt;/details&gt;
&lt;details&gt;
&lt;summary&gt;Commits&lt;/summary&gt;

&lt;ul&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@433840821a5d2a2308eb84a53bac95efdfacbe7c&quot;&gt;&lt;code&gt;4338408&lt;/code&gt;&lt;/a&gt; release 20.8.1&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@e13ea2a7c65f233df0bc526ae073c01747258de8&quot;&gt;&lt;code&gt;e13ea2a&lt;/code&gt;&lt;/a&gt; During seeding properly uninstall present versions of the wheels (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2186&quot;&gt;#2186&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@3b9d95481a7bb8ce98bc3118416ba6cbbedf99b4&quot;&gt;&lt;code&gt;3b9d954&lt;/code&gt;&lt;/a&gt; Bump embed setuptools to 58.1.0 (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2195&quot;&gt;#2195&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@40d2f1833bab94fa2cad852c5b9e31d42c66d570&quot;&gt;&lt;code&gt;40d2f18&lt;/code&gt;&lt;/a&gt; Fail early instead of creating non-working env (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2189&quot;&gt;#2189&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@9e03c945fbf22cb1384d944f874180292c1018d4&quot;&gt;&lt;code&gt;9e03c94&lt;/code&gt;&lt;/a&gt; [pre-commit.ci] pre-commit autoupdate (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2192&quot;&gt;#2192&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@2151d385094c4f320cd2484eb9bcf3272cea2cc3&quot;&gt;&lt;code&gt;2151d38&lt;/code&gt;&lt;/a&gt; Improve prompt nushell (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2190&quot;&gt;#2190&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@d810ce1c0613d1b955576bca644335b7a00b5bc0&quot;&gt;&lt;code&gt;d810ce1&lt;/code&gt;&lt;/a&gt; Merge pull request &lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2184&quot;&gt;#2184&lt;/a&gt; from pypa/release-20.8.0&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@c54c7efe172adb206c75cc1499cf8625b19064e8&quot;&gt;&lt;code&gt;c54c7ef&lt;/code&gt;&lt;/a&gt; release 20.8.0&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@e0410cafc8feedf72562174dee983fc709a5a36e&quot;&gt;&lt;code&gt;e0410ca&lt;/code&gt;&lt;/a&gt; Nushell activation scripts (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2170&quot;&gt;#2170&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;pypa/virtualenv@1cc503bfadc2c0e8c3ecac6c0a3f430ee601d9a0&quot;&gt;&lt;code&gt;1cc503b&lt;/code&gt;&lt;/a&gt; Bump pip and setuptools (&lt;a href=&quot;https://github-redirect.dependabot.com/pypa/virtualenv/issues/2183&quot;&gt;#2183&lt;/a&gt;)&lt;/li&gt;
&lt;li&gt;Additional commits viewable in &lt;a href=&quot;pypa/virtualenv@20.7.2...20.8.1&quot;&gt;compare view&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;
&lt;/details&gt;

&lt;br /&gt;
</code></pre>


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</details>

.github/workflows/constraints.txt

@@ -2,4 +2,4 @@ pip==21.2.4
 nox==2021.6.12
 nox-poetry==0.8.6
 poetry==1.1.10
-virtualenv==20.7.2
+virtualenv==20.8.1