[PM] Use `twox_64_concat` hash function for `MarketIdsPer*`

[maltekliemann]

I don't really see how users have much control over the keys here.

[sea212]

since we use incrementing timeframes or block numbers, it can be the more lightweight but less secure twox_64_concat. However, the change requires a storage migration. The optimization is not needed yet, hence I agree with the low priority on this.