build(deps): bump ujson from 5.12.0 to 5.12.1

Bumps [ujson](https://github.com/ultrajson/ultrajson) from 5.12.0 to 5.12.1.
- [Release notes](https://github.com/ultrajson/ultrajson/releases)
- [Commits](ultrajson/ultrajson@5.12.0...5.12.1)

---
updated-dependencies:
- dependency-name: ujson
  dependency-version: 5.12.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

pyproject.toml

@@ -115,7 +115,7 @@ dependencies = [
   "types-requests==2.32.4.20250611",
   "typing-inspection==0.4.2",
   "typing_extensions==4.15.0",
-  "ujson==5.12.0",
+  "ujson==5.12.1",
   "urllib3==2.6.3",
   "uvicorn==0.35.0",
   "zipp==3.23.0",