build(deps): update fastapi requirement from ~=0.115.6 to ~=0.115.11

Updates the requirements on [fastapi](https://github.com/fastapi/fastapi) to permit the latest version.
- [Release notes](https://github.com/fastapi/fastapi/releases)
- [Commits](fastapi/fastapi@0.115.6...0.115.11)

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

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

Author: dependabot[bot]

requirements.txt

@@ -9,5 +9,5 @@ sentencepiece~=0.2.0
 setuptools~=75.6.0
 huggingface-hub~=0.29.2
 transformers~=4.48.0
-fastapi~=0.115.6
+fastapi~=0.115.11
 uvicorn~=0.34.0