Bump httpx[http2] from 0.28.0 to 0.28.1 in /src (#55)

Bumps [httpx[http2]](https://github.com/encode/httpx) from 0.28.0 to 0.28.1.
- [Release notes](https://github.com/encode/httpx/releases)
- [Changelog](https://github.com/encode/httpx/blob/master/CHANGELOG.md)
- [Commits](encode/httpx@0.28.0...0.28.1)

---
updated-dependencies:
- dependency-name: httpx[http2]
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/requirements.txt

@@ -21,7 +21,7 @@ hpack==4.0.0
     # via h2
 httpcore==1.0.7
     # via httpx
-httpx[http2]==0.28.0
+httpx[http2]==0.28.1
     # via -r requirements.in
 hyperframe==6.0.1
     # via h2