After SERVER-83878 , unsharded timeseries can be tracked on the sharding catalog and consequently moved by the balancer using moveCollection (and therefore resharding).

However jstests/core/timeseries/timeseries_simple.js started failing consistently when running with balancer active ( sharding_jscore_passthrough_with_balancer) as in case a resharding operation happens during the insertions, the bucket collection will end up with more then 1 collection. 

There is no data loss, simply the compression seems not to be optimal as the test expected only 1 collection.

The check has been temporarily disabled in case of balancer enabled until this ticket is fixed.