Testing /routes/... triggers possible Express error (ReferenceError: setImmediate is not defined)

[Meryldominguez]

Describe the bug
When I run jest routes/lots there are two tests that fail, giving the wrong status code.
Upon examination and debugging, It is a problem with
return next(err) (backend/middleware.js line 56)
Before that line, the error is 401 Unauthorized as expected, but after in the general error handler (backend/app.js) it is a 500 Server error ("ReferenceError: setImmediate is not defined")

Ive done a bunch of research on this and can't find anyone having this problem...

To Reproduce
Steps to reproduce the behavior:

1. add console.log(err) to line 35 backend/app.js
2. add console.log(err) to line 58 backend/middleware/auth.js
3. jest routes/lots.test.js
4. See the two errors per failed test, one a 401 Unauthorized, the second a 500 with the ReferenceError issue

[Meryldominguez]

ALSO includes jest routes/props and jest routes/productions last two delete routes

Same problem as above, doesn't hang Jest

[Meryldominguez]

jest routes/auth --detectOpenHandles also triggers the setImmediate is not defined but leaves jest hanging