build(deps): bump chromadb from 1.0.20 to 1.1.0 in /backend

Bumps [chromadb](https://github.com/chroma-core/chroma) from 1.0.20 to 1.1.0.
- [Release notes](https://github.com/chroma-core/chroma/releases)
- [Changelog](https://github.com/chroma-core/chroma/blob/main/RELEASE_PROCESS.md)
- [Commits](https://github.com/chroma-core/chroma/compare/1.0.20...1.1.0)

---
updated-dependencies:
- dependency-name: chromadb
  dependency-version: 1.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

backend/requirements.txt

@@ -57,7 +57,7 @@ langchain==0.3.27
 langchain-community==0.3.29
 
 fake-useragent==2.2.0
-chromadb==1.0.20
+chromadb==1.1.0
 opensearch-py==2.8.0
 
 pymilvus==2.5.0