python: bump mkdocs-rss-plugin from 1.13.1 to 1.13.3 (#1376)

Bumps [mkdocs-rss-plugin](https://github.com/Guts/mkdocs-rss-plugin) from 1.13.1 to 1.13.3.
- [Release notes](https://github.com/Guts/mkdocs-rss-plugin/releases)
- [Changelog](https://github.com/Guts/mkdocs-rss-plugin/blob/main/CHANGELOG.md)
- [Commits](Guts/mkdocs-rss-plugin@1.13.1...1.13.3)

---
updated-dependencies:
- dependency-name: mkdocs-rss-plugin
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements.txt

@@ -3,4 +3,4 @@ mkdocs==1.6.0
 mkdocs-material==9.5.27
 pymdown-extensions==10.8.1
 mkdocs-minify-plugin==0.8.0
-mkdocs-rss-plugin==1.13.1
+mkdocs-rss-plugin==1.13.3