fix tests

Author: ChrisRackauckas

test/runtests.jl

@@ -1,12 +1,13 @@
 using ArrayInterface, Test
-
+import ArrayInterface: has_sparsestruct, findstructralnz
 @test ArrayInterface.ismutable(rand(3))
 
 using StaticArrays
 @test ArrayInterface.ismutable(@SVector [1,2,3]) == false
 @test ArrayInterface.ismutable(@MVector [1,2,3]) == true
 
 using LinearAlgebra, SparseArrays
+
 D=Diagonal([1,2,3,4])
 @test has_sparsestruct(D)
 rowind,colind=findstructralnz(D)