Update sphinx-autodoc-typehints requirement from ~=2.0.0 to ~=2.1.0

Updates the requirements on [sphinx-autodoc-typehints](https://github.com/tox-dev/sphinx-autodoc-typehints) to permit the latest version.
- [Release notes](https://github.com/tox-dev/sphinx-autodoc-typehints/releases)
- [Changelog](https://github.com/tox-dev/sphinx-autodoc-typehints/blob/main/CHANGELOG.md)
- [Commits](tox-dev/sphinx-autodoc-typehints@2.0.0...2.1.0)

---
updated-dependencies:
- dependency-name: sphinx-autodoc-typehints
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -59,7 +59,7 @@ ci = [
 ]
 docs = [
     'recommonmark~=0.7.1',
-    'sphinx-autodoc-typehints~=2.0.0',
+    'sphinx-autodoc-typehints~=2.1.0',
     'sphinx-copybutton~=0.5.2',
     'sphinx-markdown-tables~=0.0.17',
     'sphinx-rtd-theme~=2.0.0',