Remove unused settings (#2095)

Signed-off-by: Nczs007 <czs@alumni.hust.edu.cn>

shards/mishards/service_handler.py

@@ -10,7 +10,7 @@ from milvus.grpc_gen.milvus_pb2 import TopKQueryResult
 from milvus.client import types as Types
 from milvus import MetricType
 
-from mishards import (db, settings, exceptions)
+from mishards import (db, exceptions)
 from mishards.grpc_utils import mark_grpc_method
 from mishards.grpc_utils.grpc_args_parser import GrpcArgsParser as Parser
 from mishards import utilities