Generalize definition

Author: mtfishman

src/blocksparsearrayinterface/blocksparsearrayinterface.jl

@@ -100,7 +100,7 @@ struct BlockSparseArrayInterface <: AbstractBlockSparseArrayInterface end
   error("Not implemented")
 
 @interface ::AbstractBlockSparseArrayInterface function SparseArraysBase.isstored(
-   a::AnyAbstractBlockSparseArray{<:Any,N}, I::Vararg{Int,N}
+   a::AbstractArray{<:Any,N}, I::Vararg{Int,N}
  ) where {N}
    bI = BlockIndex(findblockindex.(axes(a), I))
    return isstored(blocks_a, bI.I...) && isstored(blocks_a[bI.I...], bI.α...)