CI: run git-clang-format until there are no more changes

That might format more code at once, but should avoid
a CI loop.

Author: dschwoerer

.github/workflows/clang-format.yml

@@ -22,7 +22,11 @@ jobs:
 
       - name: Run clang-format
         id: format
-        run: 'git clang-format origin/${{ github.base_ref }} || :'
+        run:
+          while ! git clang-format origin/${{ github.base_ref }}
+          do
+            true
+          done
 
       - name: Commit to the PR branch
         uses: stefanzweifel/git-auto-commit-action@v5