Bump h2 from 4.1.0 to 4.3.0

Bumps [h2](https://github.com/python-hyper/h2) from 4.1.0 to 4.3.0.
- [Changelog](https://github.com/python-hyper/h2/blob/master/CHANGELOG.rst)
- [Commits](python-hyper/h2@v4.1.0...v4.3.0)

---
updated-dependencies:
- dependency-name: h2
  dependency-version: 4.3.0
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -35,5 +35,5 @@ dev = [
   "sphinx>=7.2.6,<7.3; python_version >= '3.9'", # for building docs
   "websockets>=13.1",                            # for tests
   # for tests, restrict to exact version for test_http_client/TestClientMockServer/_on_remote_settings_changed that relies on the implementation details. Also, this is no needs to update this package.
-  "h2==4.1.0",
+  "h2==4.3.0",
 ]