test: Add IPC wake-up test and reuse mining context (PR #34727) - Follow-up 2 of 2 #316
Description
mentioned in: bitcoin#34727
"> If you feel like adding another followup commit, it would be good to scale waits (waitNext, etc) with the test suite timeout scaling factor. For background see bitcoin-core/libmultiprocess#253 (comment)
Sounds good, would work to add a followup commit with these changes" - enirox001