ENH: Update pre-commit settings adding "mixed-line-ending"

Replaces or checks mixed line ending.
See https://github.com/pre-commit/pre-commit-hooks?tab=readme-ov-file#mixed-line-ending

.pre-commit-config.yaml

@@ -9,6 +9,7 @@ repos:
   - id: check-toml
   - id: check-yaml
   - id: debug-statements
+  - id: mixed-line-ending
   - id: trailing-whitespace
 
 - repo: https://github.com/astral-sh/ruff-pre-commit