Update to Gunicorn 23.0.0

This commit will update/upgrade Gunicorn from 22.0.0 to 23.0.0.
[Changes](https://docs.gunicorn.org/en/latest/news.html) include
a fix for a high-severity security vulnerability (CVE-2024-1135,
[GHSA-w3h3-4rj7-4ph4](GHSA-w3h3-4rj7-4ph4)).
There are several breaking changes noted in the Gunicorn changelog.
Users are encouraged to review these changes and update usage as needed.

pyproject.toml

@@ -21,7 +21,7 @@ classifiers = [
   "Typing :: Typed",
 ]
 dependencies = [
-  "gunicorn==22.0.0",
+  "gunicorn==23.0.0",
   "uvicorn==0.28.1",
 ]
 description = "Docker images and utilities to power your Python APIs and help you ship faster."