Bump pip from 21.1.1 to 21.1.2 (PR #2969)

Bumps [pip](https://github.com/pypa/pip) from 21.1.1 to 21.1.2.
<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>21.1.2 (2021-05-23)</h1>
<h2>Bug Fixes</h2>
<ul>
<li>New resolver: Correctly exclude an already installed package if its version is
known to be incompatible to stop the dependency resolution process with a clear
error message. (<code>[#9841](pypa/pip#9841) &lt;https://github.com/pypa/pip/issues/9841&gt;</code>_)</li>
<li>Allow ZIP to archive files with timestamps earlier than 1980. (<code>[#9910](pypa/pip#9910) &lt;https://github.com/pypa/pip/issues/9910&gt;</code>_)</li>
<li>Emit clearer error message when a project root does not contain either
<code>pyproject.toml</code>, <code>setup.py</code> or <code>setup.cfg</code>. (<code>[#9944](pypa/pip#9944) &lt;https://github.com/pypa/pip/issues/9944&gt;</code>_)</li>
<li>Fix detection of existing standalone pip instance for PEP 517 builds. (<code>[#9953](pypa/pip#9953) &lt;https://github.com/pypa/pip/issues/9953&gt;</code>_)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/pypa/pip/commit/8737f903eaa9475e1b7693e436d9bdf17e46e43a"><code>8737f90</code></a> Bump for release</li>
<li><a href="https://github.com/pypa/pip/commit/d7cf6cacdee550983686692d0d463ad493cb993d"><code>d7cf6ca</code></a> Update AUTHORS.txt</li>
<li><a href="https://github.com/pypa/pip/commit/30faa6478edbc1e54498b7cbb20111d75a96d2dd"><code>30faa64</code></a> Fix duplicate top line in NEWS.rst</li>
<li><a href="https://github.com/pypa/pip/commit/128ec362547fe11f8b3c6402687a00a06e7f6e51"><code>128ec36</code></a> Test case for backtracking an installed candidate</li>
<li><a href="https://github.com/pypa/pip/commit/729c626da75b25af0640a77efdbbfc57e567e1f9"><code>729c626</code></a> Exclude a known incompatible installed candidate</li>
<li><a href="https://github.com/pypa/pip/commit/1c31d3314c42d19b354f376991db2b33134dde5e"><code>1c31d33</code></a> Update src/pip/_internal/build_env.py</li>
<li><a href="https://github.com/pypa/pip/commit/e266aa55ac6484d33c36aee7082243edd669e2a8"><code>e266aa5</code></a> Update news/9910.bugfix.rst</li>
<li><a href="https://github.com/pypa/pip/commit/00003d5325b333290b4bcde17791ed3a489562d0"><code>00003d5</code></a> 9910 news</li>
<li><a href="https://github.com/pypa/pip/commit/d55e02c71673f4332c191cf8095360c5900f7c6e"><code>d55e02c</code></a> Set strict_timestamps=False when zip is called for isolated environment</li>
<li><a href="https://github.com/pypa/pip/commit/4f983c4476251c83bc320ebaaff0cb9b71d2e981"><code>4f983c4</code></a> Handle standalone pip creation from pip wheel</li>
<li>Additional commits viewable in <a href="https://github.com/pypa/pip/compare/21.1.1...21.1.2">compare view</a></li>
</ul>
</details>
<br />

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</details>

changelogs/unreleased/2969-dependabot.yml

@@ -0,0 +1,5 @@
+change-type: patch
+description: Bump pip from 21.1.1 to 21.1.2
+destination-branches:
+- master
+sections: {}

requirements.txt

@@ -12,7 +12,7 @@ jinja2==2.11.3
 more-itertools==8.8.0
 netifaces==0.10.9
 packaging==20.9
-pip==21.1.1
+pip==21.1.2
 ply==3.11
 pydantic==1.8.2
 pyformance==0.4