Apply fail-on-error logic to error state when user tries to set coverage-reporter-version on MacOS, which is not available there.

Author: afinetooth

Diff for: action.yml

@@ -105,7 +105,11 @@ runs:
       shell: bash
       run: |
         echo "The coverage-reporter-version parameter is not available on macOS." >&2
-        exit 1
+        if [[ "${{ inputs.fail-on-error }}" == "true" ]]; then
+          exit 1
+        else
+          exit 0
+        fi
 
     - name: Install coveralls reporter (Linux)
       if: runner.os == 'Linux'