don't commit if nothing

src/backend.py

@@ -70,9 +70,10 @@ def _backend_routine():
 
             commits.append(CommitOperationAdd(path_in_repo=path_in_repo, path_or_fileobj=local_path))
 
-        API.create_commit(
-            repo_id=RESULTS_REPO, commit_message="Add evaluation results", operations=commits, repo_type="dataset"
-        )
+        if len(commits) > 0:
+            API.create_commit(
+                repo_id=RESULTS_REPO, commit_message="Add evaluation results", operations=commits, repo_type="dataset"
+            )
 
 
 def backend_routine():