fix(library_test): add cloud login (#190)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Bug Fixes**
- Added a check to ensure successful login to the cloud service before
retrieving keys, with an error message and script exit if login fails.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Co-authored-by: Lucas Mindêllo de Andrade <lucas@mindello.com.br>

library_test.py

@@ -80,6 +80,9 @@ async def main() -> None:
     )
     cloud_keys = {}
     if cloud:
+        if not await cloud.login():
+            print("ERROR: cannot login")
+            sys.exit(2)
         cloud_keys = await cloud.get_keys(first_device["device_id"])
     print("-" * 20)
     print("Fist device Cloud info: ", cloud_keys)