Add generic launch.json for debugging unittests and running python files.

[DriesSchaumont]

Changelog

Add launch.json for debugging unittests and running python files. Includes "justMyCode": false, to also check interactions with installed libraries (e.g. scanpy)

Issue ticket number and link

~Closes #xxxx (Replace xxxx with the GitHub issue number)~

Checklist before requesting a review

• [x] I have performed a self-review of my code

• [x] Conforms to the Contributor's guide

• Check the correct box. Does this PR contain:

  • [ ] Breaking changes
  • [x] New functionality
  • [ ] Major changes
  • [ ] Minor changes
  • [ ] Bug fixes

• [x] Proposed changes are described in the CHANGELOG.md

• [x] CI tests succeed!

[DriesSchaumont]

@rcannood as an alternative, we could re-add launch.json back to .gitignore... WDYT

[rcannood]

It seems like you prefer adding the launch.json to .gitignore.... So please Add the launch.json to the .gitignore ;)