clang-tidy module: copy .gitignore from top level
Since !8364 (merged), .gitignore entries have been pinned to the top-level .gitignore file. Copy these entries into a .gitignore for the clang-tidy module.
Since !8364 (merged), .gitignore entries have been pinned to the top-level .gitignore file. Copy these entries into a .gitignore for the clang-tidy module.