Fix misc-unused-using-decls clang-tidy warning

packages/modules/Connectivity/service/native/TrafficController.cpp:58:18: error: using decl 'DumpWriter' is unused [misc-unused-using-decls,-warnings-as-errors]
using netdutils::DumpWriter;
^
packages/modules/Connectivity/service/native/TrafficController.cpp:58:18: note: remove the using
using netdutils::DumpWriter;
~~~~~~~~~~~~~~~~^~~~~~~~~~~
packages/modules/Connectivity/service/native/TrafficController.cpp:61:18: error: using decl 'ScopedIndent' is unused [misc-unused-using-decls,-warnings-as-errors]
using netdutils::ScopedIndent;
^
packages/modules/Connectivity/service/native/TrafficController.cpp:61:18: note: remove the using
using netdutils::ScopedIndent;
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~

Test: presubmit
Change-Id: I1871139fed31c57a5c15a8ab4f88aa7c695ff360
diff --git a/service/native/TrafficController.cpp b/service/native/TrafficController.cpp
index 543bdc8..8cd698e 100644
--- a/service/native/TrafficController.cpp
+++ b/service/native/TrafficController.cpp
@@ -46,7 +46,6 @@
 
 #include "TrafficController.h"
 #include "bpf/BpfMap.h"
-#include "netdutils/DumpWriter.h"
 
 namespace android {
 namespace net {
@@ -55,10 +54,8 @@
 using base::unique_fd;
 using bpf::BpfMap;
 using bpf::synchronizeKernelRCU;
-using netdutils::DumpWriter;
 using netdutils::NetlinkListener;
 using netdutils::NetlinkListenerInterface;
-using netdutils::ScopedIndent;
 using netdutils::Slice;
 using netdutils::sSyscalls;
 using netdutils::Status;