diff --git a/tests/ci/pr_info.py b/tests/ci/pr_info.py
index 5221f2a2fae..9d287d2a07e 100644
--- a/tests/ci/pr_info.py
+++ b/tests/ci/pr_info.py
@@ -220,7 +220,7 @@ class PRInfo:
         else:
             diff_object = PatchSet(response.text)
             self.changed_files = {f.path for f in diff_object}
-        print("Fetched info about %d changed files", len(self.changed_files))
+        print("Fetched info about %d changed files" % len(self.changed_files))
 
     def get_dict(self):
         return {