Bump starlette from 0.47.2 to 0.49.1 in /api-server/qna-eval

Bumps [starlette](https://github.com/Kludex/starlette) from 0.47.2 to 0.49.1.
- [Release notes](https://github.com/Kludex/starlette/releases)
- [Changelog](https://github.com/Kludex/starlette/blob/main/docs/release-notes.md)
- [Commits](Kludex/starlette@0.47.2...0.49.1)

---
updated-dependencies:
- dependency-name: starlette
  dependency-version: 0.49.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

api-server/qna-eval/requirements.txt

@@ -144,7 +144,7 @@ smart-open==7.3.0.post1
 sniffio==1.3.1
 soupsieve==2.7
 stack-data==0.6.3
-starlette==0.47.2
+starlette==0.49.1
 sympy==1.14.0
 textual==5.3.0
 tiktoken==0.11.0