chore: bump azure-keyvault-secrets in /examples/msal-python

Bumps [azure-keyvault-secrets](https://github.com/Azure/azure-sdk-for-python) from 4.3.0 to 4.7.0.
- [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-keyvault-secrets_4.3.0...azure-keyvault-secrets_4.7.0)

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

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

examples/msal-python/requirements.txt

@@ -1,2 +1,2 @@
-azure-keyvault-secrets==4.3.0
+azure-keyvault-secrets==4.7.0
 msal==1.14.0