Only upload on for Perl 5.30

Author: foursixnine

.github/workflows/ci-linux.yaml

@@ -40,8 +40,8 @@ jobs:
           TEST_SHARED=1 TEST_SUBREAPER=1 cover -test -report codecovbash
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v2
+        if: matrix.perl == '5.30'
         with:
-          perl-version: '5.30'
           file: cover_db/codecov.json
           fail_ci_if_error: true
           verbose: true