fix: fix `Base.length` for empty `ArrayPartition`, add tests#363

ChrisRackauckas merged 1 commit intoSciML:masterSciML/RecursiveArrayTools.jl:masterfrom

AayushSabharwal:as/arraypartition-lengthAayushSabharwal/RecursiveArrayTools.jl:as/arraypartition-lengthCopy head branch name to clipboard