chore: bump pytest-regtest from 2.1.1 to 2.2.1

Bumps [pytest-regtest](https://gitlab.com/uweschmitt/pytest-regtest) from 2.1.1 to 2.2.1.
- [Commits](https://gitlab.com/uweschmitt/pytest-regtest/commits/2.2.1)

---
updated-dependencies:
- dependency-name: pytest-regtest
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>