Remove db service fields from gateway_info_v2

src/service/mobile_config.proto

@@ -76,13 +76,6 @@ message gateway_info_v2 {
   gateway_metadata_v2 metadata = 2;
   // the asserted device type of the gateway
   device_type device_type = 3;
-  // The Unix epoch timestamp (in seconds)
-  // when the data was read from the chain and written to the database.
-  // It does not necessarily mean that anything was changed in the gateway.
-  uint64 refreshed_at = 4;
-  // The unix epoch timestamp (in seconds)
-  // when the gateway was first added to the database.
-  uint64 created_at = 5;
 }
 
 message gateway_info_req_v1 {