Bump pytest from 6.2.0 to 6.2.1 (#551)

Bumps [pytest](https://github.com/pytest-dev/pytest) from 6.2.0 to 6.2.1.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/pytest-dev/pytest/releases">pytest's releases</a>.</em></p>
<blockquote>
<h2>6.2.1</h2>
<h1>pytest 6.2.1 (2020-12-15)</h1>
<h2>Bug Fixes</h2>
<ul>
<li>
<p><a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/7678">#7678</a>: Fixed bug where <code>ImportPathMismatchError</code> would be raised for files compiled in
the host and loaded later from an UNC mounted path (Windows).</p>
</li>
<li>
<p><a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8132">#8132</a>: Fixed regression in <code>approx</code>: in 6.2.0 <code>approx</code> no longer raises
<code>TypeError</code> when dealing with non-numeric types, falling back to normal comparison.
Before 6.2.0, array types like tf.DeviceArray fell through to the scalar case,
and happened to compare correctly to a scalar if they had only one element.
After 6.2.0, these types began failing, because they inherited neither from
standard Python number hierarchy nor from <code>numpy.ndarray</code>.</p>
<p><code>approx</code> now converts arguments to <code>numpy.ndarray</code> if they expose the array
protocol and are not scalars. This treats array-like objects like numpy arrays,
regardless of size.</p>
</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/pytest-dev/pytest/commit/d3971c30f4d0f1890a372af3b98de41ee555dcb3"><code>d3971c3</code></a> Prepare release version 6.2.1</li>
<li><a href="https://github.com/pytest-dev/pytest/commit/780044b64a79eb99eb08d86a08d5cf7fa8b047ba"><code>780044b</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8147">#8147</a> from nicoddemus/backport-8137</li>
<li><a href="https://github.com/pytest-dev/pytest/commit/8354995abc4c4f913a8266fb53b7d2a4e93e4050"><code>8354995</code></a> python_api: handle array-like args in approx() (<a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8137">#8137</a>)</li>
<li><a href="https://github.com/pytest-dev/pytest/commit/8b8b1214f4834419a5f45758d6cdc4eddba01359"><code>8b8b121</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8135">#8135</a> from nicoddemus/backport-8123</li>
<li><a href="https://github.com/pytest-dev/pytest/commit/f854cf66f4ad866d27f85e6fcc3b476a835ca3e7"><code>f854cf6</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8123">#8123</a> from nicoddemus/import-mismatch-unc</li>
<li><a href="https://github.com/pytest-dev/pytest/commit/c475106f12ed87fe908544ff383c5205638c086d"><code>c475106</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/pytest-dev/pytest/issues/8130">#8130</a> from pytest-dev/release-6.2.0</li>
<li>See full diff in <a href="https://github.com/pytest-dev/pytest/compare/6.2.0...6.2.1">compare view</a></li>
</ul>
</details>
<br />


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Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`.

[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)

requirements/test.txt

@@ -1,5 +1,5 @@
 pytest-cov>=2.3.1
-pytest==6.2.0
+pytest==6.2.1
 multidict==5.1.0
 idna==2.10
 typing_extensions==3.7.4.2;python_version<"3.8"