Bump the pip group across 1 directory with 2 updates

Updates the requirements on [haystack-ai](https://github.com/deepset-ai/haystack) and [starlette](https://github.com/encode/starlette) to permit the latest version.

Updates `haystack-ai` from 2.0.0b5 to 2.3.1
- [Release notes](https://github.com/deepset-ai/haystack/releases)
- [Commits](deepset-ai/haystack@v2.0.0-beta.5...v2.3.1)

Updates `starlette` to 0.41.2
- [Release notes](https://github.com/encode/starlette/releases)
- [Changelog](https://github.com/encode/starlette/blob/master/docs/release-notes.md)
- [Commits](encode/starlette@0.1.0...0.41.2)

---
updated-dependencies:
- dependency-name: haystack-ai
  dependency-type: direct:production
  dependency-group: pip
- dependency-name: starlette
  dependency-type: direct:production
  dependency-group: pip
...

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

requirements.txt

@@ -10,7 +10,7 @@ distro==1.9.0
 fastapi==0.109.1
 google-search-results
 h11==0.14.0
-haystack-ai==2.0.0b5
+haystack-ai==2.3.1
 haystack-bm25==1.0.2
 httpcore==1.0.2
 httptools==0.6.1
@@ -37,7 +37,7 @@ requests==2.32.2
 sentence-transformers==2.3.1
 six==1.16.0
 sniffio==1.3.0
-starlette<0.38.0
+starlette<0.42.0
 tenacity==8.2.3
 torch==2.2.0
 tqdm==4.66.3