Bump h11 from 0.14.0 to 0.16.0 in /app/backend

Bumps [h11](https://github.com/python-hyper/h11) from 0.14.0 to 0.16.0.
- [Commits](python-hyper/h11@v0.14.0...v0.16.0)

---
updated-dependencies:
- dependency-name: h11
  dependency-version: 0.16.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

app/backend/requirements.txt

@@ -13,7 +13,7 @@ click==8.1.7
 colorama==0.4.6
 cryptography==44.0.1
 Flask==3.0.1
-h11==0.14.0
+h11==0.16.0
 h2==4.1.0
 hpack==4.0.0
 Hypercorn==0.16.0