chore(deps): bump bleach in /run/markdown-preview/renderer

Bumps [bleach](https://github.com/mozilla/bleach) from 6.2.0 to 6.4.0.
- [Changelog](https://github.com/mozilla/bleach/blob/main/CHANGES)
- [Commits](mozilla/bleach@v6.2.0...v6.4.0)

---
updated-dependencies:
- dependency-name: bleach
  dependency-version: 6.4.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

run/markdown-preview/renderer/requirements.txt

@@ -1,6 +1,6 @@
 Flask==3.1.3; python_version >= '3.9'
 gunicorn==23.0.0
 Markdown==3.7
-bleach==6.2.0; python_version >= "3.9"
+bleach==6.4.0; python_version >= "3.9"
 bleach==6.1.0; python_version <= "3.8"
 Werkzeug==3.1.8; python_version >= '3.9'