pip: bump docutils from 0.18.1 to 0.21.1

Bumps [docutils](https://docutils.sourceforge.io) from 0.18.1 to 0.21.1.

---
updated-dependencies:
- dependency-name: docutils
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@ Babel==2.14.0
 certifi==2024.2.2
 charset-normalizer==3.3.2
 click==8.1.7
-docutils==0.18.1
+docutils==0.21.1
 idna==3.7
 imagesize==1.4.1
 Jinja2==3.1.3