refactor: user different top_k number to reflect upgrades made to rel… (#1527)

… db migration

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examples/python/relational_database_migration_example.py

@@ -70,23 +70,23 @@ async def main():
     search_results = await cognee.search(
         query_type=SearchType.GRAPH_COMPLETION,
         query_text="What kind of data do you contain?",
-        top_k=1000,
+        top_k=200,
     )
     print(f"Search results: {search_results}")
 
     # Having a top_k value set to too high might overwhelm the LLM context when specific questions need to be answered.
-    # For this kind of question we've set the top_k to 30
+    # For this kind of question we've set the top_k to 50
     search_results = await cognee.search(
         query_type=SearchType.GRAPH_COMPLETION,
         query_text="What invoices are related to Leonie Köhler?",
-        top_k=30,
+        top_k=50,
     )
     print(f"Search results: {search_results}")
 
     search_results = await cognee.search(
         query_type=SearchType.GRAPH_COMPLETION,
         query_text="What invoices are related to Luís Gonçalves?",
-        top_k=30,
+        top_k=50,
     )
     print(f"Search results: {search_results}")