chore: address github-code-quality findings

lib/cli/tests/test_plus_api.py

@@ -17,7 +17,7 @@ class TestPlusAPI(unittest.TestCase):
         self.assertEqual(self.api.api_key, self.api_key)
         self.assertEqual(self.api.headers["Authorization"], f"Bearer {self.api_key}")
         self.assertEqual(self.api.headers["Content-Type"], "application/json")
-        self.assertTrue("CrewAI-CLI/" in self.api.headers["User-Agent"])
+        self.assertIn("CrewAI-CLI/", self.api.headers["User-Agent"])
         self.assertTrue(self.api.headers["X-Crewai-Version"])
 
     @patch("crewai_cli.plus_api.PlusAPI._make_request")

lib/cli/tests/test_token_manager.py

@@ -1,7 +1,6 @@
 """Tests for TokenManager with atomic file operations."""
 
 import json
-import os
 import tempfile
 import unittest
 from datetime import datetime, timedelta