Prevent infinite scheduling loop
Prevent infinite scheduling loop

One shard might be able to run a compaction, but could fail to
limits being hit.  This loop would continue indefinitely as the
same task would continue to be rescheduled.

linearb/influxdb,influxdb/influxdb,nooproblem/influxdb,benbjohnson/influxdb,mark-rushakoff/influxdb,influxdata/influxdb,vladlopes/influxdb,benbjohnson/influxdb,influxdb/influxdb,vladlopes/influxdb,linearb/influxdb,nooproblem/influxdb,influxdb/influxdb,nooproblem/influxdb,influxdb/influxdb,vladlopes/influxdb,vladlopes/influxdb,mark-rushakoff/influxdb,linearb/influxdb,mark-rushakoff/influxdb,linearb/influxdb,influxdata/influxdb,influxdb/influxdb,benbjohnson/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb,linearb/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,li-ang/influxdb,li-ang/influxdb,benbjohnson/influxdb,mark-rushakoff/influxdb,nooproblem/influxdb