Bump docutils from 0.17.1 to 0.18.1

Bumps [docutils](http://docutils.sourceforge.net/) from 0.17.1 to 0.18.1.

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

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

setup.cfg

@@ -60,7 +60,7 @@ dev =
 
 doc =
     Sphinx==4.3.1
-    docutils==0.17.1
+    docutils==0.18.1
     myst-parser
 
 [options.entry_points]