Intermitent failure: : test access scanner - 'ep_num_access_scanner_skips' to be 8 (last value:4) - aborting.

Running [31/156]: test access scanner...Exceeded maximum wait time of 60000000us waiting for stat 'ep_num_access_scanner_skips' to be 8 (last value:4) - aborting. 

https://cv.jenkins.couchbase.com/job/kv_engine.linux-debug/job/master/6196/

I believe this issue occurs because the access scanner has ran before we read ep_num_access_scanner_skips.

Instrumenting for this test I note that at that failing check I always see ep_num_access_scanner_skip=0, thus the wait_for code is waiting until that stat hits 4.

In the failure we see ep_num_access_scanner_skips=4 and we're waiting for 8, which makes me think we're racing with the access scanner.