reformat source code

according to code styles, 'AccessModifierOffset' should be -2.

unittest/share/test_alive_server_tracer.cpp

@@ -79,7 +79,7 @@ TEST(TestAliveServerMap, all)
 }
 
 class ServerList {
-  public:
+public:
   int fetch_alive_server(const ObFetchAliveServerArg&, ObFetchAliveServerResult& res, const ObRpcOpts&)
   {
     return res.server_list_.assign(server_list_);