Run test that require db access (#5796)

as mongo only.

also seperate out into own section of test.

spec/ParseUser.spec.js

@@ -3847,8 +3847,12 @@ describe('Parse.User testing', () => {
       }
     );
   });
+});
 
-  it('should validate credentials first and check if account already linked afterwards (GHSA-8w3j-g983-8jh5)', async done => {
+describe('Security Advisory GHSA-8w3j-g983-8jh5', function() {
+  it_only_db('mongo')(
+    'should validate credentials first and check if account already linked afterwards ()',
+    async done => {
       // Add User to Database with authData
       const database = Config.get(Parse.applicationId).database;
       const collection = await database.adapter._adaptiveCollection('_User');
@@ -3883,5 +3887,6 @@ describe('Parse.User testing', () => {
       }
       fail();
       done();
-  });
+    }
+  );
 });