Bump pytest-cov from 2.11.1 to 2.12.0 (#597)

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 2.11.1 to 2.12.0.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst">pytest-cov's changelog</a>.</em></p>
<blockquote>
<h2>2.12.0 (2021-05-14)</h2>
<ul>
<li>Added coverage's <code>toml</code> extra to install requirements in setup.py.
Contributed by Christian Riedel in <code>[#410](pytest-dev/pytest-cov#410) &lt;https://github.com/pytest-dev/pytest-cov/pull/410&gt;</code>_.</li>
<li>Fixed <code>pytest_cov.__version__</code> to have the right value (string with version instead of a string
including <code>__version__ =</code>).</li>
<li>Fixed license classifier in <code>setup.py</code>.
Contributed by Chris Sreesangkom in <code>[#467](pytest-dev/pytest-cov#467) &lt;https://github.com/pytest-dev/pytest-cov/pull/467&gt;</code>_.</li>
<li>Fixed <em>commits since</em> badge.
Contributed by Terence Honles in <code>[#470](pytest-dev/pytest-cov#470) &lt;https://github.com/pytest-dev/pytest-cov/pull/470&gt;</code>_.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/9692bad8c3501b77cf950d0732ae9cb5c8bb0bd4"><code>9692bad</code></a> Bump version: 2.11.1 → 2.12.0</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/f533121b78d479ee4bf0c3c09b48d9513523ffb1"><code>f533121</code></a> Update changelog.</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/62d2e94debe6230e0160b1d5f711ae7f42158e9f"><code>62d2e94</code></a> Fix configuration file, ref f2ee249.</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/f2ee249e7214b9cad53f56fe33b6c8012a8ef08e"><code>f2ee249</code></a> fix link in readme (<a href="https://github-redirect.dependabot.com/pytest-dev/pytest-cov/issues/470">#470</a>)</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/f5a4d7e008087913ce2bc9dc2305d05a5f545a41"><code>f5a4d7e</code></a> Fix version value. Fixes <a href="https://github-redirect.dependabot.com/pytest-dev/pytest-cov/issues/468">#468</a>.</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/2cd009442ddb08dc873117019b13ef972803d5c4"><code>2cd0094</code></a> change in setup.py from BSD to MIT to match LICENSE file (<a href="https://github-redirect.dependabot.com/pytest-dev/pytest-cov/issues/467">#467</a>)</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/daf54e79fcb8f549699d28e691302a9251f7e54b"><code>daf54e7</code></a> Added toml as extra (<a href="https://github-redirect.dependabot.com/pytest-dev/pytest-cov/issues/410">#410</a>)</li>
<li><a href="https://github.com/pytest-dev/pytest-cov/commit/c2dfa778a85c1f64f3f59007b8d8ca98c877cac8"><code>c2dfa77</code></a> Update test deps. Remove unnecessary assertion. Closes <a href="https://github-redirect.dependabot.com/pytest-dev/pytest-cov/issues/452">#452</a>.</li>
<li>See full diff in <a href="https://github.com/pytest-dev/pytest-cov/compare/v2.11.1...v2.12.0">compare view</a></li>
</ul>
</details>
<br />


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requirements/pytest.txt

@@ -1,2 +1,2 @@
 pytest==6.2.4
-pytest-cov==2.11.1
+pytest-cov==2.12.0