Fix build-ripunzip.yml archive step on macos

Author: redsun82

.github/workflows/build-ripunzip.yml

@@ -96,7 +96,7 @@ jobs:
       - name: Archive
         shell: bash
         run: |
-          tar acf ripunzip-$RUNNER_OS.tar.zst ripunzip-${RUNNER_OS,,}
+          tar acf ripunzip-$RUNNER_OS.tar.zst ripunzip-$(echo $RUNNER_OS | tr '[:upper:]' '[:lower:]')
       - name: Upload built binary
         uses: actions/upload-artifact@v4
         with: