chore: add license header (#35)

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

proto/greptime/v1/common.proto

@@ -1,3 +1,17 @@
+// Copyright 2023 Greptime Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 syntax = "proto3";
 
 package greptime.v1;
@@ -31,14 +45,8 @@ message Basic {
   string password = 2;
 }
 
-message Token {
-  string token = 1;
-}
+message Token { string token = 1; }
 
-message AffectedRows {
-  uint32 value = 1;
-}
+message AffectedRows { uint32 value = 1; }
 
-message FlightMetadata {
-  AffectedRows affected_rows = 1;
-}
+message FlightMetadata { AffectedRows affected_rows = 1; }