made function non async

Author: shubanker

test/schema.test.js

@@ -2682,8 +2682,8 @@ describe('schema', function() {
     assert.equal(TestSchema.path('testprop.$*').instance, 'Number');
     assert.equal(TestSchema.path('testprop.$*').options.ref, 'OtherModel');
   });
-  
-  it('disallows setting special properties with `add()` or constructor (gh-12085)', async function() {
+
+  it('disallows setting special properties with `add()` or constructor (gh-12085)', function() {
     const maliciousPayload = '{"__proto__.toString": "Number"}';
 
     assert.throws(() => {