### Changes

**Fix `uvicorn[standard]` version** (be409c4)

Uvicorn was updated to version 0.23.2 in 2590d8a and 0.56.0, but the
version number for `uvicorn[standard]` was not updated correspondingly.
This release will update `uvicorn[standard]` to 0.23.2.

**Update to Material for MkDocs 9** (ab692a3, 90f75b0)

Docs will now be built with
[Material for MkDocs 9](https://squidfunk.github.io/mkdocs-material/changelog/).
The most notable user-facing change is the new dark theme color palette,
which has undergone a few small changes since its release in version
9.4.0 (https://github.com/squidfunk/mkdocs-material/issues/6061).
Code block copy behavior has undergone some small changes as well. Code
blocks in the documentation have been reformatted for easier copying.

### Commits

- Bump version from 0.56.0 to 0.56.1 (0dba457)
- Fix `uvicorn[standard]` version (be409c4)
- Add docs deployment info to contributing.md (141d8e5)
- Remove Material for MkDocs version from README (b415bf4)
- Configure Material for MkDocs code block copy (90f75b0)
- Update to Material for MkDocs 9 (ab692a3)
- Relax upper bound on HTTPX (f49d205)
- Update to `mypy==1.7.0` (140dac6)
- Update changelog for version 0.56.0 (#86) (18f2052)