.gitlab-ci.yml: Fix the recommended reformat command

.gitlab-ci.yml

@@ -86,7 +86,7 @@ check-code-format:
         -name "*.cc" -print0 \
       | xargs -0 -I {} -P $(nproc) \
         clang-format --dry-run --Werror {} \
-      || (echo -e 'Run the following command to fix format:\nfind . -name "*.h" -print0 -or -name "*.cc" | xargs -0 -I {} clang-format -i {}' \
+      || (echo -e 'Run the following command to fix format:\nfind . -name "*.h" -print0 -or -name "*.cc" -print0 | xargs -0 -I {} clang-format -i {}' \
       && exit 1)
 
 lint: