Bump azure-identity from 1.7.1 to 1.16.1 in /docs (#9)

Bumps [azure-identity](https://github.com/Azure/azure-sdk-for-python) from 1.7.1 to 1.16.1.
- [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_1.7.1...azure-identity_1.16.1)

---
updated-dependencies:
- dependency-name: azure-identity
  dependency-type: direct:production
...

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

docs/requirements.txt

@@ -2,7 +2,7 @@ semantic-link-sempy
 sphinx_rtd_theme
 pandas==2.0.3
 # pyspark==3.5.0
-azure-identity==1.7.1
+azure-identity==1.16.1
 azure-keyvault-secrets
 azure-storage-file-datalake==12.3.1
 azure-storage-blob>=12.9.0