Simplify test module docstring per review feedback

Drop the detailed description from the test_management.py docstring,
keeping only the general module-level summary.

Author: mykaul

tests/unit/cqlengine/test_management.py

@@ -14,10 +14,6 @@
 
 """
 Unit tests for cassandra.cqlengine.management module.
-
-Focuses on verifying that _get_table_metadata gracefully handles missing
-table metadata by forcing a targeted refresh and retrying, and that
-_sync_table delegates to _get_table_metadata for post-DDL metadata lookup.
 """
 
 import unittest