Update pytest-cov requirement from <4.1,>=3.0 to >=3.0,<4.2 (#279)

Updates the requirements on
[pytest-cov](https://github.com/pytest-dev/pytest-cov) to permit the
latest version.
<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>4.1.0 (2023-05-24)</h2>
<ul>
<li>Updated CI with new Pythons and dependencies.</li>
<li>Removed rsyncdir support. This makes pytest-cov compatible with
xdist 3.0.
Contributed by Sorin Sbarnea in
<code>[#558](pytest-dev/pytest-cov#558)
&lt;https://github.com/pytest-dev/pytest-cov/pull/558&gt;</code>_.</li>
<li>Optimized summary generation to not be performed if no reporting is
active (for example,
when <code>--cov-report=''</code> is used without
<code>--cov-fail-under</code>).
Contributed by Jonathan Stewmon in
<code>[#589](pytest-dev/pytest-cov#589)
&lt;https://github.com/pytest-dev/pytest-cov/pull/589&gt;</code>_.</li>
<li>Added support for JSON reporting.
Contributed by Matthew Gamble in
<code>[#582](pytest-dev/pytest-cov#582)
&lt;https://github.com/pytest-dev/pytest-cov/pull/582&gt;</code>_.</li>
<li>Refactored code to use f-strings.
Contributed by Mark Mayo in
<code>[#572](pytest-dev/pytest-cov#572)
&lt;https://github.com/pytest-dev/pytest-cov/pull/572&gt;</code>_.</li>
<li>Fixed a skip in the test suite for some old xdist.
Contributed by a bunch of people in
<code>[#565](pytest-dev/pytest-cov#565)
&lt;https://github.com/pytest-dev/pytest-cov/pull/565&gt;</code>_.</li>
</ul>
<h2>4.0.0 (2022-09-28)</h2>
<p><strong>Note that this release drops support for
multiprocessing.</strong></p>
<ul>
<li>
<p><code>--cov-fail-under</code> no longer causes <code>pytest
--collect-only</code> to fail
Contributed by Zac Hatfield-Dodds in
<code>[#511](pytest-dev/pytest-cov#511)
&lt;https://github.com/pytest-dev/pytest-cov/pull/511&gt;</code>_.</p>
</li>
<li>
<p>Dropped support for multiprocessing (mostly because <code>issue 82408
&lt;https://github.com/python/cpython/issues/82408&gt;</code>_). This
feature was
mostly working but very broken in certain scenarios and made the test
suite very flaky and slow.</p>
<p>There is builtin multiprocessing support in coverage and you can
migrate to that. All you need is this in your
<code>.coveragerc</code>::</p>
<p>[run]
concurrency = multiprocessing
parallel = true
sigterm = true</p>
</li>
<li>
<p>Fixed deprecation in <code>setup.py</code> by trying to import
setuptools before distutils.
Contributed by Ben Greiner in
<code>[#545](pytest-dev/pytest-cov#545)
&lt;https://github.com/pytest-dev/pytest-cov/pull/545&gt;</code>_.</p>
</li>
<li>
<p>Removed undesirable new lines that were displayed while reporting was
disabled.
Contributed by Delgan in
<code>[#540](pytest-dev/pytest-cov#540)
&lt;https://github.com/pytest-dev/pytest-cov/pull/540&gt;</code>_.</p>
</li>
<li>
<p>Documentation fixes.
Contributed by Andre Brisco in
<code>[#543](pytest-dev/pytest-cov#543)
&lt;https://github.com/pytest-dev/pytest-cov/pull/543&gt;</code>_
and Colin O'Dell in
<code>[#525](pytest-dev/pytest-cov#525)
&lt;https://github.com/pytest-dev/pytest-cov/pull/525&gt;</code>_.</p>
</li>
<li>
<p>Added support for LCOV output format via
<code>--cov-report=lcov</code>. Only works with coverage 6.3+.
Contributed by Christian Fetzer in
<code>[#536](pytest-dev/pytest-cov#536)
&lt;https://github.com/pytest-dev/pytest-cov/issues/536&gt;</code>_.</p>
</li>
<li>
<p>Modernized pytest hook implementation.
Contributed by Bruno Oliveira in
<code>[#549](pytest-dev/pytest-cov#549)
&lt;https://github.com/pytest-dev/pytest-cov/pull/549&gt;</code>_
and Ronny Pfannschmidt in
<code>[#550](pytest-dev/pytest-cov#550)
&lt;https://github.com/pytest-dev/pytest-cov/pull/550&gt;</code>_.</p>
</li>
</ul>
<p>3.0.0 (2021-10-04)</p>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/2c9f2170d8575b21bafb6402eb30ca7de31e20b9"><code>2c9f217</code></a>
Bump version: 4.0.0 → 4.1.0</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/4d245df8f75e434a9e1b162b51265d6a45017465"><code>4d245df</code></a>
Update changelog and authors.</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/7b095c84ae521b14058d7d520ef36372849063a8"><code>7b095c8</code></a>
Skip starting from xdist 3.0.2 (where boxed was removed).</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/605d6902b3b3d17aad0bf811b8c580fc895724ca"><code>605d690</code></a>
disabling boxed test if version xdist newer than 2.5.0</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/76fb2a6cb2c4a4a788a5b62710848daf9c8fb7ce"><code>76fb2a6</code></a>
introduced f-strings</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/0d63ede0d2ca9f4acc8329aa4261a7cec489ffdb"><code>0d63ede</code></a>
Update test config. Reapply some of the changes from PR567 to the right
file ...</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/f3d8d8380f6a4b265353fe7cd509b040702f1e64"><code>f3d8d83</code></a>
Add support for JSON reporter</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/dec02abeb9fa8ee3547baa054bde6006bea530ee"><code>dec02ab</code></a>
Update test deps.</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/88a7d348986bace58e26c88a713ef35f900ce2ef"><code>88a7d34</code></a>
chore: update AUTHORS and CHANGELOG</li>
<li><a
href="https://github.com/pytest-dev/pytest-cov/commit/74eb4cc8b684269b89735e31b623f0f9795c5d5c"><code>74eb4cc</code></a>
perf: only call summary when the report will be used</li>
<li>Additional commits viewable in <a
href="https://github.com/pytest-dev/pytest-cov/compare/v3.0.0...v4.1.0">compare
view</a></li>
</ul>
</details>
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</details>

requirements/testing.txt

@@ -2,5 +2,5 @@
 # --------------------
 
 pillow>=9.4,<10
-pytest-cov>=3.0,<4.1
+pytest-cov>=3.0,<4.2
 validators>=0.19,<0.21