Add pre-commit hook for validating release notes

- This is a pre-commit hook using `pre-commit` framework to validate release notes YAML files.
- The hook checks for correct structure, formatting and required fields in the `release-notes` directory.
- This ensures consistency and correctness in release notes before committing changes.

Ref: #934 (comment)

.pre-commit-config.yaml

@@ -0,0 +1,8 @@
+repos:
+-   repo: local
+    hooks:
+    -   id: validate-release-notes
+        name: Validate Release Notes
+        entry: python ci/check-release-notes.py
+        language: python
+        files: ^release-notes/.*\.yml$