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## Summary
From my reading of the [UV
docs](https://docs.astral.sh/uv/guides/scripts/), `mirror.py` would be a
good example of a standalone script. This PR updates `mirror.py` and the
`main.yml` workflow to be a UV script and makes use of UV in the update
process.
## Test Plan
- Update the uv version (currently 0.8.4) to an older version e.g. 0.8.3
in both `pyproject.toml` and `README.md`
- Run `uv run --no-project mirror.py` to check the update process still
works as expected
## Summary
Starting with version 0.5.0 of Ruff, the release/tag name doesn't have a
leading "v". This has broken the link to the release notes that get
added to the release notes for the pre-commit hook.
This fixes it by stripping any "v" from the version number string.
See #91.
## Test Plan
Tested in a bash shell:
```bash
bash-5.2$ TAG_NAME=v0.5.0
bash-5.2$ echo ${TAG_NAME/v}
0.5.0
```
Will otherwise have to be tested on the next Ruff release.
