test: fix two flaky tests (darwin start_time regex, memstats HeapReleased drift)#2050

bwplotka merged 2 commits into

prometheus:mainprometheus/client_golang:mainfrom

kakkoyun:kakkoyun/fix-darwin-start-timekakkoyun/client_golang:kakkoyun/fix-darwin-start-timeCopy head branch name to clipboard