Speed-up on MoveWorker spec

[mjankowski]

Reduces spec run time from ~17s to ~9s, and reduces DB queries in spec from ~15,400 to ~11,100.

There are probably more improvements to be found in this one, but it's all pretty deeply nested and this was the most obvious low hanging fruit for a first pass.

Good future work here could include:

• Look at whether the block/mute shared example could be combined with the followers one (they are always called together)
• Look through the various permutations of shared example nesting and identify which ones do/dont need all the data created, and try to isolate that better. There are almost definitely examples here creating way more data then they need, but its hard to sort out with the nesting.