chore: update codecov/codecov-action to v4

[vil02]

Description

Toneless uploads to codecov are no longer supported. This PR updates codecov/codecov-action to v4 and changes the upload workflow in such a way that:

• tokenless upload it used for PRs created from forks,
• upload with token is used for every other occasion.

Before merge: please make sure to add the token as CODECOV_TOKEN into the repo secrets. (Token was added)

It seems that both of the branches work:

• tokenless,
• without token - the job has failed due to the lack of the token in my fork, but the branch was correctly selected.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (17d5dad) 94.68% compared to head (1ba8b44) 94.68%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #670   +/-   ##
=======================================
  Coverage   94.68%   94.68%           
=======================================
  Files         292      292           
  Lines       23258    23258           
=======================================
  Hits        22022    22022           
  Misses       1236     1236           

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[vil02]

@siriak: I think you can merge it. My strong conjecture is that the push will go through the upload with token branch.

[vil02]

@siriak thanks! I just checked, everything works as expected.