src: allow running tasks without Environment

There is no real reason to assume that V8 tasks would have
to run in a Node.js `Context`.

PR-URL: nodejs#26376
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node_platform.cc

@@ -334,9 +334,13 @@ void PerIsolatePlatformData::RunForegroundTask(std::unique_ptr<Task> task) {
   Isolate* isolate = Isolate::GetCurrent();
   HandleScope scope(isolate);
   Environment* env = Environment::GetCurrent(isolate);
-  InternalCallbackScope cb_scope(env, Local<Object>(), { 0, 0 },
-                                 InternalCallbackScope::kAllowEmptyResource);
-  task->Run();
+  if (env != nullptr) {
+    InternalCallbackScope cb_scope(env, Local<Object>(), { 0, 0 },
+                                   InternalCallbackScope::kAllowEmptyResource);
+    task->Run();
+  } else {
+    task->Run();
+  }
 }
 
 void PerIsolatePlatformData::DeleteFromScheduledTasks(DelayedTask* task) {