Add CODEOWNERS to end-of-file-fixer and trailing-whitespace

Author: hugovk

.pre-commit-config.yaml

@@ -45,10 +45,12 @@ repos:
       - id: end-of-file-fixer
         types: [python]
         exclude: Lib/test/tokenizedata/coding20731.py
+      - id: end-of-file-fixer
+        files: ^\.github/CODEOWNERS
       - id: trailing-whitespace
         types_or: [c, inc, python, rst]
       - id: trailing-whitespace
-        files: '\.(gram)$'
+        files: '^\.github/CODEOWNERS|\.(gram)$'
 
   - repo: https://github.com/python-jsonschema/check-jsonschema
     rev: 0.33.0