chore: fix flaky sample track_objects (#211)

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Fixes #<issue_number_goes_here> 🦕

packages/google-cloud-videointelligence/samples/analyze/analyze.py

@@ -425,7 +425,7 @@ def track_objects_gcs(gcs_uri):
     )
     print("\nProcessing video for object annotations.")
 
-    result = operation.result(timeout=300)
+    result = operation.result(timeout=500)
     print("\nFinished processing.\n")
 
     # The first result is retrieved because a single video was processed.
@@ -480,7 +480,7 @@ def track_objects(path):
     )
     print("\nProcessing video for object annotations.")
 
-    result = operation.result(timeout=300)
+    result = operation.result(timeout=500)
     print("\nFinished processing.\n")
 
     # The first result is retrieved because a single video was processed.