Context canceled while uploading visit-mark.json #5332
Description
Describe the bug
We saw a lot of failed bucket operations when uploading visit-mark.json due to context canceled error.
markBlocksVisitedHeartBeat is running in a separate goroutine and its lifecycle is controled by the context of planner.
And in the mark blocks visited loop https://github.com/cortexproject/cortex/blob/master/pkg/compactor/block_visit_marker.go#L127,
we are trying to upload markers first then check whether context is canceled or not.
It is possible to have context already canceled and we are trying to upload markers and failed. After that we check context and exit. This cause bucket operations fail when uploading markers.