Makes codecov-action optional (#1130)

We do not want to fail the job if codecov fails
to upload the report due to rate limiting.

Signed-off-by: Mikalai Radchuk <[email protected]>

Author: m1kola

staging/operator-registry/.github/workflows/unit.yaml

@@ -22,5 +22,4 @@ jobs:
       - uses: codecov/codecov-action@v3
         with:
           files: coverage.out
-          fail_ci_if_error: true
           functionalities: fixes