Build(deps): bump ujson in /frameworks/Python/fastapi

Bumps [ujson](https://github.com/ultrajson/ultrajson) from 5.10.0 to 5.12.0.
- [Release notes](https://github.com/ultrajson/ultrajson/releases)
- [Commits](ultrajson/ultrajson@5.10.0...5.12.0)

---
updated-dependencies:
- dependency-name: ujson
  dependency-version: 5.12.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

frameworks/Python/fastapi/requirements.txt

@@ -1,5 +1,5 @@
 fastapi==0.126
 asyncpg==0.31.0; implementation_name=='cpython'
 Jinja2==3.1.6
-ujson==5.10.0
+ujson==5.12.0
 orjson==3.11.6; implementation_name=='cpython'