As per today evergreen defines a specific suite to run FSM workloads related to the concurrent execution of addShard and removeShard, but very limited coverage is guaranteed by that, considering that:

• the suite includes a single test- the main purpose of such a test is to ensure the consistent execution of the $currentOp and $changestream aggregation stages
• in order to avoid spurious errors, the outcome of addShard goes unchecked

The objective of this ticket is to adapt and extend the coverage over addShard and removeShard ensured by the suite.