src: avoid unnecessarily formatting a warning

ProcessEmitWarning will already format the message, there is no
need to call snprintf here.

PR-URL: #21832
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node_file.cc

@@ -172,13 +172,11 @@ inline void FileHandle::Close() {
   // to notify that the file descriptor was gc'd. We want to be noisy about
   // this because not explicitly closing the FileHandle is a bug.
   env()->SetUnrefImmediate([](Environment* env, void* data) {
-    char msg[70];
     err_detail* detail = static_cast<err_detail*>(data);
-    snprintf(msg, arraysize(msg),
-            "Closing file descriptor %d on garbage collection",
-            detail->fd);
+    ProcessEmitWarning(env,
+                       "Closing file descriptor %d on garbage collection",
+                       detail->fd);
     delete detail;
-    ProcessEmitWarning(env, msg);
   }, detail);
 }