feat: show exact diff of needed reformatting

Co-authored-by: Ramy <[email protected]>

Author: vil02

.github/workflows/check_code_format.yml

@@ -33,4 +33,8 @@ jobs:
              git status --porcelain=v1
              exit 1
           fi
+
+      - name: Exact diff of needed reformatting
+        if: failure()
+        run: git diff
 ...