Add release workflow

[bmario]

With the added Citation.cff file, which needs updating for every release, we should think about a github actions workflow for the release.

Current, manual steps:

1. Update CMakeLists.txt
2. Create Version bump commit
3. Create a new release that tags the version bump commit and manually add a changelog (and/or generate parts of the changelog using the button)

New step:

• Update citations.cff

[bmario]

See also #319