[8.3] Wrap error message in quotes

Co-authored-by: Seth Michael Larson <[email protected]>

Author: github-actions[bot]

.github/workflows/metamodel-sync.yml

@@ -20,4 +20,4 @@ jobs:
 
     - name: Check file sync
       run: |
-        if [ -n "$(git status --porcelain)" ]; then echo Error: compiler's metamodel and ts generator metamodel are not in sync; git diff; git status; exit 1; fi
+        if [ -n "$(git status --porcelain)" ]; then echo "Error: compiler's metamodel and ts generator metamodel are not in sync"; git diff; git status; exit 1; fi