[CI] update codecov action to v4

[kasia-kujawa]

Description: update codecov action to v4

Link to tracking Issue: #32259

[crobert-1]

It looks like to add support for v4 we'd need to add a token for this action. (v4 breaking change reference.)

Workflow changes unfortunately aren't picked up in their respective PR, so this failure wouldn't be hit until this gets merged into main, from my understanding. Some workflow changes aren't picked up (like CODEOWNERS), but this one appears to be.

[crobert-1]

Well it looks like the action actually passed here. I admit I'm a bit confused as to what's going on. I see from the output:

info - 2024-04-09 15:49:49,207 -- The PR is happening in a forked repo. Using tokenless upload.

So maybe it did pick up your changes, but it's not requiring a token since the PR is a fork? But if this gets merged main will fail with the token error, perhaps?

[kasia-kujawa]

Well it looks like the action actually passed here. I admit I'm a bit confused as to what's going on. I see from the output:
info - 2024-04-09 15:49:49,207 -- The PR is happening in a forked repo. Using tokenless upload.
So maybe it did pick up your changes, but it's not requiring a token since the PR is a fork? But if this gets merged main will fail with the token error, perhaps?

@crobert-1 I wasn't sure if token is required for this repo seeing this information

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)

but definitely it is better to add this.

I need a help with adding the secret with token for this repo, link to the instruction for generating token is here.

[kasia-kujawa]

As this is closed open-telemetry/community#1926 so I expect that the CODECOV_TOKEN secret exists