Bump prometheus-client from 0.20.0 to 0.21.0 (#17746)

Bumps [prometheus-client](https://github.com/prometheus/client_python)
from 0.20.0 to 0.21.0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/prometheus/client_python/releases">prometheus-client's
releases</a>.</em></p>
<blockquote>
<h2>0.21.0 / 2024-09-20</h2>
<h2>What's Changed</h2>
<p>[CHANGE] Reject invalid (not GET or OPTION) HTTP methods. <a
href="https://redirect.github.com/prometheus/client_python/issues/1019">#1019</a>
[ENHANCEMENT] Allow writing metrics when holding a lock for the metric
in the same thread. <a
href="https://redirect.github.com/prometheus/client_python/issues/1014">#1014</a>
[BUGFIX] Check for and error on None label values. <a
href="https://redirect.github.com/prometheus/client_python/issues/1012">#1012</a>
[BUGFIX] Fix timestamp comparison. <a
href="https://redirect.github.com/prometheus/client_python/issues/1038">#1038</a></p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="3b183b4499"><code>3b183b4</code></a>
Release 0.21.0</li>
<li><a
href="0014e97763"><code>0014e97</code></a>
Use re-entrant lock. (<a
href="https://redirect.github.com/prometheus/client_python/issues/1014">#1014</a>)</li>
<li><a
href="7c45f84e5e"><code>7c45f84</code></a>
Reject invalid HTTP methods and resources (<a
href="https://redirect.github.com/prometheus/client_python/issues/1019">#1019</a>)</li>
<li><a
href="09a5ae3060"><code>09a5ae3</code></a>
Fix timestamp comparison (<a
href="https://redirect.github.com/prometheus/client_python/issues/1038">#1038</a>)</li>
<li><a
href="e364a96f50"><code>e364a96</code></a>
Fix a typo in ASGI docs (<a
href="https://redirect.github.com/prometheus/client_python/issues/1036">#1036</a>)</li>
<li><a
href="eeec421b2f"><code>eeec421</code></a>
Pin python 3.8 and 3.9 at patch level (<a
href="https://redirect.github.com/prometheus/client_python/issues/1024">#1024</a>)</li>
<li><a
href="7bc8cddfbb"><code>7bc8cdd</code></a>
docs: correct link to multiprocessing docs (<a
href="https://redirect.github.com/prometheus/client_python/issues/1023">#1023</a>)</li>
<li><a
href="4535ce0f43"><code>4535ce0</code></a>
Add sanity check for label value (<a
href="https://redirect.github.com/prometheus/client_python/issues/1012">#1012</a>)</li>
<li>See full diff in <a
href="https://github.com/prometheus/client_python/compare/v0.20.0...v0.21.0">compare
view</a></li>
</ul>
</details>
<br />


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poetry.lock

@@ -1569,13 +1569,13 @@ files = [
 
 [[package]]
 name = "prometheus-client"
-version = "0.20.0"
+version = "0.21.0"
 description = "Python client for the Prometheus monitoring system."
 optional = false
 python-versions = ">=3.8"
 files = [
-    {file = "prometheus_client-0.20.0-py3-none-any.whl", hash = "sha256:cde524a85bce83ca359cc837f28b8c0db5cac7aa653a588fd7e84ba061c329e7"},
-    {file = "prometheus_client-0.20.0.tar.gz", hash = "sha256:287629d00b147a32dcb2be0b9df905da599b2d82f80377083ec8463309a4bb89"},
+    {file = "prometheus_client-0.21.0-py3-none-any.whl", hash = "sha256:4fa6b4dd0ac16d58bb587c04b1caae65b8c5043e85f778f42f5f632f6af2e166"},
+    {file = "prometheus_client-0.21.0.tar.gz", hash = "sha256:96c83c606b71ff2b0a433c98889d275f51ffec6c5e267de37c7a2b5c9aa9233e"},
 ]
 
 [package.extras]