Bump pyansys-sphinx-theme from 0.2.3 to 0.3.0 in /requirements (#1137)

Bumps [pyansys-sphinx-theme](https://github.com/pyansys/pyansys-sphinx-theme) from 0.2.3 to 0.3.0.
- [Release notes](https://github.com/pyansys/pyansys-sphinx-theme/releases)
- [Commits](ansys/ansys-sphinx-theme@v0.2.3...v0.3.0)

---
updated-dependencies:
- dependency-name: pyansys-sphinx-theme
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

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

Author: dependabot[bot]

requirements/requirements_docs.txt

@@ -8,7 +8,7 @@ matplotlib==3.5.2
 numpydoc==1.3.1
 pandas==1.4.2
 plotly==5.8.0
-pyansys_sphinx_theme==0.2.3
+pyansys_sphinx_theme==0.3.0
 pypandoc==1.8.1
 pytest-sphinx==0.4.0
 pythreejs==2.3.0