build(deps): bump scikit-learn to 1.9.0 in search-api

Bumps [scikit-learn](https://github.com/scikit-learn/scikit-learn) from 1.7.1 to 1.9.0.
- [Release notes](https://github.com/scikit-learn/scikit-learn/releases)
- [Commits](scikit-learn/scikit-learn@1.7.1...1.9.0)

---
updated-dependencies:
- dependency-name: scikit-learn
  dependency-version: 1.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

search-api/requirements.txt

@@ -7,6 +7,6 @@ numpy==2.4.6
 psycopg2-binary==2.9.10
 requests==2.33.1
 redis==8.0.0
-scikit-learn==1.7.1
+scikit-learn==1.9.0
 sentence-transformers==5.4.1
 transformers==5.8.0