build(deps): bump urllib3 in /samples/server/petstore/python-fastapi

Bumps [urllib3](https://github.com/urllib3/urllib3) from 2.6.0 to 2.6.3.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@2.6.0...2.6.3)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-version: 2.6.3
  dependency-type: direct:production
...

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

Author: dependabot[bot]

samples/server/petstore/python-fastapi/requirements.txt

@@ -29,7 +29,7 @@ Rx==1.6.1
 starlette==0.49.1
 typing-extensions==4.13.2
 ujson==4.0.2
-urllib3==2.6.0
+urllib3==2.6.3
 uvicorn==0.13.4
 uvloop==0.21.0
 watchgod==0.7