Bump azure-identity from 1.17.1 to 1.18.0

Bumps [azure-identity](https://github.com/Azure/azure-sdk-for-python) from 1.17.1 to 1.18.0.
- [Release notes](https://github.com/Azure/azure-sdk-for-python/releases)
- [Changelog](https://github.com/Azure/azure-sdk-for-python/blob/main/doc/esrp_release.md)
- [Commits](Azure/azure-sdk-for-python@azure-identity_1.17.1...azure-identity_1.18.0)

---
updated-dependencies:
- dependency-name: azure-identity
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -8,7 +8,7 @@ langchain==0.2.16
 langchain-openai==0.1.23
 langchain-community==0.2.12
 azure-search-documents==11.5.1
-azure-identity==1.17.1
+azure-identity==1.18.0
 azure-ai-documentintelligence==1.0.0b4
 azure-storage-blob==12.22.0
 requests==2.32.3