Update httpx requirement from ~=0.27.2 to ~=0.28.0

Updates the requirements on [httpx](https://github.com/encode/httpx) to permit the latest version.
- [Release notes](https://github.com/encode/httpx/releases)
- [Changelog](https://github.com/encode/httpx/blob/master/CHANGELOG.md)
- [Commits](encode/httpx@0.27.2...0.28.0)

---
updated-dependencies:
- dependency-name: httpx
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -7,7 +7,7 @@ requires-python = ">=3.11"
 dependencies = [
     "beautifulsoup4~=4.12.3",
     "fastapi~=0.115.2",
-    "httpx~=0.27.2",
+    "httpx~=0.28.0",
     "jinja2~=3.1.4",
     "pydantic-settings~=2.6.0",
     "pydantic>=2.7.0,<3.0.0",