This continues the push of plumbing contexts through tendermint. I
attempted to find all goroutines in the production code (non-test) and
made sure that these threads would exit when their contexts were
canceled, and I believe this PR does that.
This code hasn't been battle tested, and seems to have grown
increasingly flaky int tests. Given our general direction of reducing
queue complexity over the next couple of releases I think it makes
sense to remove it.
This adds a test for closing the `pqueue` while the `pqueue` contains data that has not yet been dequeued.
This issue was found while debugging #6705
This test will fail until @cmwaters fix for this condition is merged.
