Make codecov project check informational and only fail on patch check

If a change overall removes lines and those lines were all covered, project coverage will be reduced.

This should not be a failure if patch coverage is good. Ideally we would allow project coverage to fail only if patch coverage is 100%, but I don't think that is possible.

This can be configured in codevcov.yaml: https://docs.codecov.com/docs/commit-status

Thoughts?

Start by inspecting the repository's codevcov.yaml configuration and the linked Codecov commit-status documentation. Check how the project and patch checks are currently configured; done means project coverage is informational while patch coverage remains the failing check, subject to the stated limitation about requiring 100% patch coverage.

索引モデルが issue の本文から書いたものです。