Log Message:
py-h2: update to 4.2.0.

4.2.0 (2025-02-01)
------------------

**API Changes (Backward Incompatible)**

- Support for Python 3.6 has been removed.
- Support for Python 3.7 has been removed.
- Support for Python 3.8 has been removed.
- Remove mistakenly set `max_inbound_frame_size` attribute on `H2Stream`.

**API Changes (Backward Compatible)**

- Support for Python 3.11 has been added.
- Support for Python 3.12 has been added.
- Support for Python 3.13 has been added.
- Add an ability to send outbound cookies separately to improve headers compression.
- Updated packaging and testing infrastructure.

**Bugfixes**

- Fix repr() checks for Python 3.11
- Fix asyncio / wsgi examples.
- Clarify docs on using curl with http2.