[BUG] Job fails, but reports as successful

Describe the bug

When the codecov job fails, Github Actions reports it as a successful job, with a green check mark, but if I click into the job I see that there was indeed a fatal error.

See here for example: https://github.com/phpgt/CssXPath/actions/runs/23646541739/job/68880104526#step:5:260

The log shows the following (not the last line):

==> Running upload-coverage
      ./codecov  upload-coverage -t <redacted> --git-service github --gcov-executable gcov
info - 2026-03-27 12:38:34,416 -- ci service found: github-actions
warning - 2026-03-27 12:38:34,425 -- No config file could be found. Ignoring config.
warning - 2026-03-27 12:38:34,457 -- xcrun is not installed or can't be found.
warning - 2026-03-27 12:38:34,460 -- No gcov data found.
warning - 2026-03-27 12:38:34,460 -- coverage.py is not installed or can't be found.
info - 2026-03-27 12:38:34,476 -- Found 2 coverage files to report
info - 2026-03-27 12:38:34,477 -- > /home/runner/work/CssXPath/CssXPath/_coverage/clover.xml
info - 2026-03-27 12:38:34,477 -- > /home/runner/work/CssXPath/CssXPath/_coverage/coverage.txt
info - 2026-03-27 12:38:34,860 -- Upload queued for processing complete
error - 2026-03-27 12:38:34,860 -- Upload queued for processing failed: {"message":"Repository not found"}

But take a look at the status of the job - success!

To Reproduce

1. Push code to trigger the codecov Github Action
2. View the job executing
3. See it pass with a green check mark
4. View the job log, see that there was in fact an error

Expected behavior

When there's an error running the job, mark the job as failed. Such as one that shows this as the last line of the log: error - 2026-03-27 12:38:34,860 -- Upload queued for processing failed: {"message":"Repository not found"}

Product Area

Coverage. I am sending my PHPUnit coverage to codecov. I do it with all my open source repositories. The reason there's a failure is a different issue to track. This issue is just tracking the fact that there was a failure, but it reported as a success.

Start by inspecting the codecov GitHub Action entry point that runs the upload command and the linked GitHub Actions job log, focusing on how upload errors affect the process status. Done means a fatal upload error such as the reported repository-not-found message causes the workflow job to fail instead of showing a successful check.