src: disallow JS execution during exit()

This is just an extra safeguard – no JS should run once we’ve
decided that we are going to shutdown the process, but we’re opening
a handle scope in order to access V8, so make sure that our operations
do not lead to JS accidentally being run.

PR-URL: #35020
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Shelley Vohr <codebytere@gmail.com>

src/env.cc

@@ -964,6 +964,8 @@ uv_key_t Environment::thread_local_env = {};
 void Environment::Exit(int exit_code) {
   if (options()->trace_exit) {
     HandleScope handle_scope(isolate());
+    Isolate::DisallowJavascriptExecutionScope disallow_js(
+        isolate(), Isolate::DisallowJavascriptExecutionScope::CRASH_ON_FAILURE);
 
     if (is_main_thread()) {
       fprintf(stderr, "(node:%d) ", uv_os_getpid());