add model for async-execute

javascript/ql/src/semmle/javascript/frameworks/SystemCommandExecutors.qll

@@ -43,9 +43,15 @@ private predicate execApi(string mod, int cmdArg, int optionsArg, boolean shell)
   )
   or
   shell = true and
-  mod = "exec" and
-  optionsArg = -2 and
-  cmdArg = 0
+  (
+    mod = "exec" and
+    optionsArg = -2 and
+    cmdArg = 0
+    or
+    mod = "async-execute" and
+    optionsArg = 1 and
+    cmdArg = 0
+  )
 }
 
 private class SystemCommandExecutors extends SystemCommandExecution, DataFlow::InvokeNode {