Stricter regex and safer YAML

Co-authored-by: Adam Turner <[email protected]>

Author: hugovk

.pre-commit-config.yaml

@@ -46,7 +46,7 @@ repos:
         types_or: [python, yaml]
         exclude: Lib/test/tokenizedata/coding20731.py
       - id: end-of-file-fixer
-        files: ^\.github/CODEOWNERS
+        files: '^\.github/CODEOWNERS$'
       - id: trailing-whitespace
         types_or: [c, inc, python, rst, yaml]
       - id: trailing-whitespace