Enable ruff `UP007`

[fpgmaas]

Proposed changes

Enable UP007 for this project. According to PEP563, by importing from __future__ import annotations, starting with Python 3.7 the annotations should be backwards compatible.

Types of changes

What types of changes does your code introduce to quinn? Put an x in the boxes that apply

• [x] Bugfix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation Update (if none of the other choices apply)

[SemyonSinchenko]

@fpgmaas Thank you for the contribution! In the planning 1.0 release we dropped the support of py37 and already enabled Ruff. May you reopen this PR into the planning-1.0-release branch? The idea is that the current main accepts only fixes.

[SemyonSinchenko]

@fpgmaas Than you for your work!