src: remove unnecessary 'Local.As' operation

PR-URL: #32286
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node_env_var.cc

@@ -269,7 +269,7 @@ Maybe<bool> KVStore::AssignFromObject(Local<Context> context,
 
     Local<Value> value;
     Local<String> value_string;
-    if (!entries->Get(context, key.As<String>()).ToLocal(&value) ||
+    if (!entries->Get(context, key).ToLocal(&value) ||
         !value->ToString(context).ToLocal(&value_string)) {
       return Nothing<bool>();
     }