Update github actions to codecov v4.

[aljones15]

not sure if the codecov token is set.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.77%. Comparing base (4cd1f8e) to head (20aa72d).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #177   +/-   ##
=======================================
  Coverage   88.77%   88.77%           
=======================================
  Files           4        4           
  Lines         811      811           
=======================================
  Hits          720      720           
  Misses         91       91           

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[davidlehn]

• The same thing is in update-vc-2.0 already. Does it need to be in main as well?
• It's an org level secret so should work with all repos.

[aljones15]

• The same thing is in update-vc-2.0 already. Does it need to be in main as well?
• It's an org level secret so should work with all repos.

We don't know when update-vc-2.0 will hit main so yeah I think it's better to do it here and not further clog up the update-vc-2.0 PR. p.s. I didn't know it was also in upgrade-vc-2.0

[davidlehn]

It's not really clogging up anything. But feel free to merge. I think dave's commit in the other branch will get dropped on a rebase.