Replace explicit codecov token with tokenless-OIDC authentication (#1406)

See hazelcast/hazelcast-csharp-client#1031

Author: JackPGreen

.github/workflows/coverage-report.yaml

@@ -29,7 +29,7 @@ jobs:
       - name: Publish on Codecov
         uses: codecov/codecov-action@v5
         with:
-          token: ${{ secrets.CODECOV_TOKEN }}
+          use_oidc: true
           files: coverage.info
           disable_search: 'true'
           fail_ci_if_error: true