Other: Run pre-commit only on staged changes

[Davknapp]

Closes #1466

Updates the pre-commit script to do the following:

• Check the size of the git stash
• run git stash to stash un-commited changes
• Check the size again to see if sth has actually been stashed
• If so print a warning message
• Run the pre-commit script as usually
• if something has been stash, pop the stash.

############### QUESTION #################
Should we also include untracked files to the stash?

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.97%. Comparing base (322342b) to head (a993b06).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2182   +/-   ##
=======================================
  Coverage   77.97%   77.97%           
=======================================
  Files         113      113           
  Lines       19106    19106           
=======================================
  Hits        14898    14898           
  Misses       4208     4208           

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[sandro-elsweijer]

I don't know when exactly the pre-commit is performed. If it is really before the commit, this will also stash the added changes which this script should control

[sandro-elsweijer]

About the question: If they are not added then yes :)

[sandro-elsweijer]

I don't know when exactly the pre-commit is performed. If it is really before the commit, this will also stash the added changes which this script should control

Nvm, I did not know about the --keep-index option

[Davknapp]

I don't know when exactly the pre-commit is performed. If it is really before the commit, this will also stash the added changes which this script should control

The pre-commit is performed when you execute "git commit", befor the commit is created. It sits between "git add" and "git commit".