Bump ansys-sphinx-theme from 0.9.8 to 0.9.9

Bumps [ansys-sphinx-theme](https://github.com/ansys/ansys-sphinx-theme) from 0.9.8 to 0.9.9.
- [Release notes](https://github.com/ansys/ansys-sphinx-theme/releases)
- [Commits](ansys/ansys-sphinx-theme@v0.9.8...v0.9.9)

---
updated-dependencies:
- dependency-name: ansys-sphinx-theme
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]