Downstream agda-stdlib changes (related to lemmas about lists) #563
Description
When agda/agda-stdlib#2479 is merged, which port stdlib additions from this repo, the task is to update the stdlib dependency and remove all these lemmas/definitions about lists:
Data/List/Ext.agdaData/List/Ext/Properties.agdaData/List/Relation/Binary/Sublist/Ext.agdaData/List/Relation/Unary/Unique/Propositional/Properties/WithK.agda