open handles potentially keeping Jest from exiting: in lambda context() mocking

When I try to run test with jest I encountered following error.

import context from 'aws-lambda-mock-context'

 it("Normal case",async ()=>{
            const irohaResponse= registered;
            jest.spyOn(IrohaTransactionExec.prototype,"exec").mockReturnValue(Promise.resolve(irohaResponse))
            const event = forbidden_shop_request as any
            expect(await handler(event,context(),()=>{})).toStrictEqual(response)
        },10000)

it seems that mock context() is open in this case.. I would like to root cause an how to fix it. If someone has opinion, will you please let me know . thanks

jest --detectOpenHandles --forceExit

Jest has detected the following 2 open handles potentially keeping Jest from exiting:

  ●  Timeout

      30 |             jest.spyOn(IrohaTransactionExec.prototype,"exec").mockReturnValue(Promise.resolve(irohaResponse))
      31 |             const event = forbidden_shop_request as any
    > 32 |             expect(await handler(event,context(),()=>{})).toStrictEqual(response)
         |                                               ^
      33 |         },10000)
      34 |         it("Normal case",async ()=>{
      35 |             const irohaResponse= registered;

      at Object.<anonymous>.module.exports (../../../../node_modules/aws-lambda-mock-context/index.js:66:2)
      at Object.<anonymous> (test/functions/transactions/handler.spec.ts:32:47)