The pre-commit hooks do not work on macOS

```console
$ grep "entry.*python" .pre-commit-config.yaml
        entry: 'python Tools/patchcheck/reindent.py --nobackup --newline LF'
        entry: "python Tools/patchcheck/untabify.py"
```

Unfortunately, there is no `python` on macOS; only `python3`. Can we change these to `python3`?


### Linked PRs
* gh-110653