Enable new module search algorithm for GCE/Flex/opensource/other.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185766513

Author: emrekultursay

src/googleclouddebugger/__init__.py

@@ -52,7 +52,7 @@ def _StartDebugger():
 
   _hub_client = gcp_hub_client.GcpHubClient()
   visibility_policy = _GetVisibilityPolicy()
-  use_new_module_search = _flags.get('use_new_module_search')
+  use_new_module_search = _flags.get('use_new_module_search', True)
 
   _breakpoints_manager = breakpoints_manager.BreakpointsManager(
       _hub_client,