src: remove unused variables

These have been overlooked in 036fbdb.

PR-URL: #23880
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Eugene Ostroukhov <eostroukhov@google.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Matheus Marchini <mat@mmarchini.me>

src/node_trace_events.cc

@@ -62,7 +62,6 @@ void NodeCategorySet::New(const FunctionCallbackInfo<Value>& args) {
 }
 
 void NodeCategorySet::Enable(const FunctionCallbackInfo<Value>& args) {
-  Environment* env = Environment::GetCurrent(args);
   NodeCategorySet* category_set;
   ASSIGN_OR_RETURN_UNWRAP(&category_set, args.Holder());
   CHECK_NOT_NULL(category_set);
@@ -74,7 +73,6 @@ void NodeCategorySet::Enable(const FunctionCallbackInfo<Value>& args) {
 }
 
 void NodeCategorySet::Disable(const FunctionCallbackInfo<Value>& args) {
-  Environment* env = Environment::GetCurrent(args);
   NodeCategorySet* category_set;
   ASSIGN_OR_RETURN_UNWRAP(&category_set, args.Holder());
   CHECK_NOT_NULL(category_set);