Fix weird pruning reporting players when they didn't actually play

[ricky-wong]

Might be able to repro this with a failed dancer-list load.

--> concord-r1: @cab1: No dancers found. Is this cookie set up correctly? redacted-cookie
Pruning data. We should see this after we have retrieved all data.
--> concord-r1: cab.players before: REMI 51539845,ROSCOE 51442388,ORANGEEE 51502133,I 51410413,TY 51410469,HUSKYSAN 51426406
--> concord-r1: cab.players after: REMI 51539845,ORANGEEE 51502133,ROSCOE 51442388,I 51410413,TY 51410469,HUSKYSAN 51426406
        > @concord-r1: + ORANGEEE 51502133
Sending message to BotTester/#tfti: ORANGEEE (51502133) was spotted at <#512433546648879134>! <:TFTI:537689355553079306>
Sending message to DDR Machine Stalking/#tfti: ORANGEEE (51502133) was spotted at <#542963959313989633>! <:TFTI:542983258728693780>
pingChannel concord-r1: + ORANGEEE    51502133
Sending message to BotTester/#concord-r1: + ORANGEEE    51502133
Sending message to San Jose DDR Players/#concord-r1: + ORANGEEE    51502133
Sending message to DDR Machine Stalking/#concord-r1: + ORANGEEE    51502133