Bump fastapi from 0.63.0 to 0.109.1 in /backend

Bumps [fastapi](https://github.com/tiangolo/fastapi) from 0.63.0 to 0.109.1.
- [Release notes](https://github.com/tiangolo/fastapi/releases)
- [Commits](fastapi/fastapi@0.63.0...0.109.1)

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

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

backend/requirements.txt

@@ -12,7 +12,7 @@ dnspython==2.0.0
 docker==4.4.4
 docker-compose==1.28.4
 email-validator==1.1.1
-fastapi==0.63.0
+fastapi==0.109.1
 fastapi-jwt-auth==0.5.0
 gunicorn==20.0.4
 h11==0.9.0