Use setuptools-scm for dynamic versioning of releases

Currently, we need to edit pyproject.toml files for both core and plugin before publishing a release.
In longer run, will be easier if this can be automated. I've forgotten do update toml files many times. 

https://github.com/pypa/setuptools-scm
 
- Configure pyproject.toml for setuptools_scm so that git tags are used for versions
- Update in github actions
 