Merge pull request #872 from xu-bin-bin/wvp-28181-2.0

删除2.6.8升级2.6.9.sql文件中给表gb_stream添加主键sql，保证升级脚本能正常执行。

sql/2.6.8升级2.6.9.sql

@@ -179,10 +179,6 @@ alter table device_mobile_position
 alter table device_mobile_position
     change createTime create_time varchar(50) null;
 
-alter table gb_stream
-    add constraint gb_stream_pk
-        primary key (gbStreamId);
-
 alter table gb_stream
     change gbStreamId gb_stream_id int auto_increment;