chore(deps): bump python-rapidjson from 1.20 to 1.21

Bumps [python-rapidjson](https://github.com/python-rapidjson/python-rapidjson) from 1.20 to 1.21.
- [Changelog](https://github.com/python-rapidjson/python-rapidjson/blob/master/CHANGES.rst)
- [Commits](python-rapidjson/python-rapidjson@v1.20...v1.21)

---
updated-dependencies:
- dependency-name: python-rapidjson
  dependency-version: '1.21'
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -2,6 +2,6 @@ fast-json==0.3.2
 orjson==3.11.1
 pyjson5==1.6.9
 pysimdjson==6.0.2 ; python_version < '3.13'
-python-rapidjson==1.20
+python-rapidjson==1.21
 simplejson==3.20.1
 ujson==5.10.0