Bump org.testcontainers:testcontainers from 1.21.2 to 1.21.3 (#431)

Bumps
[org.testcontainers:testcontainers](https://github.com/testcontainers/testcontainers-java)
from 1.21.2 to 1.21.3.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/testcontainers/testcontainers-java/releases">org.testcontainers:testcontainers's
releases</a>.</em></p>
<blockquote>
<h2>1.21.3</h2>
<h1>What's Changed</h1>
<ul>
<li>Update testcontainers/sshd version to 1.3.0 (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10377">#10377</a>)
<a
href="https://github.com/eddumelendez"><code>@​eddumelendez</code></a></li>
<li>Support docker/mcp-gateway image (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10378">#10378</a>)
<a
href="https://github.com/eddumelendez"><code>@​eddumelendez</code></a></li>
<li>Update testcontainers version to 1.21.2 (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10369">#10369</a>)
<a
href="https://github.com/github-actions"><code>@​github-actions</code></a></li>
<li>Update docs version to 1.21.2 (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10368">#10368</a>)
<a
href="https://github.com/github-actions"><code>@​github-actions</code></a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/testcontainers/testcontainers-java/commit/bebbb2c373e15e41e2faaa78632c85dc0f87b899"><code>bebbb2c</code></a>
Update testcontainers/sshd version to 1.3.0 (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10377">#10377</a>)</li>
<li><a
href="https://github.com/testcontainers/testcontainers-java/commit/2f64a4431a3e743ead728111e46754015af5f117"><code>2f64a44</code></a>
Support docker/mcp-gateway image (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10378">#10378</a>)</li>
<li><a
href="https://github.com/testcontainers/testcontainers-java/commit/b2b404a9a87ed70d0672fe5bb9ac1e3a463af94f"><code>b2b404a</code></a>
[create-pull-request] automated change (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10369">#10369</a>)</li>
<li><a
href="https://github.com/testcontainers/testcontainers-java/commit/c47afa829fe8fdbad28ac22d5a186f51b944aaa9"><code>c47afa8</code></a>
[create-pull-request] automated change (<a
href="https://redirect.github.com/testcontainers/testcontainers-java/issues/10368">#10368</a>)</li>
<li>See full diff in <a
href="https://github.com/testcontainers/testcontainers-java/compare/1.21.2...1.21.3">compare
view</a></li>
</ul>
</details>
<br />


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Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -54,7 +54,7 @@ protobuf-kotlin = { module = "com.google.protobuf:protobuf-kotlin", version.ref
 protobuf-kotlinlite = { module = "com.google.protobuf:protobuf-kotlin-lite", version.ref = "protobuf" }
 slf4j-simple = { module = "org.slf4j:slf4j-simple", version.ref = "slf4j" }
 spotless = { module = "com.diffplug.spotless:spotless-plugin-gradle", version.ref = "spotless" }
-testcontainers = { module = "org.testcontainers:testcontainers", version = "1.21.2" }
+testcontainers = { module = "org.testcontainers:testcontainers", version = "1.21.3" }
 
 [plugins]
 git = { id = "com.palantir.git-version", version = "3.3.0" }