ci: update codecov action to v4

[bnjbvr]

https://github.com/codecov/codecov-action/tree/v4?tab=readme-ov-file#v4-release

Tokenless uploading is unsupported. However, PRs made from forks to the upstream public repos will support tokenless (e.g. contributors to OS projects do not need the upstream repo's Codecov token)

Let's see if it helps with forks.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.85%. Comparing base (8392ef0) to head (7c3ede7).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3175   +/-   ##
=======================================
  Coverage   83.85%   83.85%           
=======================================
  Files         232      232           
  Lines       23938    23938           
=======================================
  Hits        20074    20074           
  Misses       3864     3864           

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[jmartinesp]

I think you probably need to add the codecov token: element-hq/element-x-android@8ce7ae6. You can find it in Codecov's setting page.

[bnjbvr]

Ah, it seems we're passing it here already: https://github.com/matrix-org/matrix-rust-sdk/pull/3175/files#diff-a2115d277b5ca5a2f09a999e53440839cf332b94da177f3d1766334555b0f7c6R118

[jmartinesp]

Maybe rebase the code so the codecov flow runs? Closing/opening doesn't seem to be doing anything.

[bnjbvr]

Oh well, I was hoping it was a fluke that would have passed over the weekend, but it doesn't seem to be. I think we should escalate this to the support team of codecov, if it happens again, because right now most of our pull requests are blocked.