tests: fix flaky "NeomakeListJobs with job cancellation"
tests: fix flaky "NeomakeListJobs with job cancellation"

Longer sleep so that job is not stopped already - happened on vim-master.

Build log: https://circleci.com/gh/neomake/neomake/24989

codeinabox/neomake,neomake/neomake,neomake/neomake