added usings to further make tests independent

Author: lostella

test/cg.jl

@@ -3,6 +3,7 @@ using LinearMaps
 using Test
 using LinearAlgebra
 using SparseArrays
+using Random
 
 import LinearAlgebra.ldiv!
 

test/gmres.jl

@@ -3,6 +3,7 @@ using Test
 using LinearMaps
 using LinearAlgebra
 using Random
+using SparseArrays
 
 #GMRES
 @testset "GMRES" begin

test/minres.jl

@@ -1,5 +1,8 @@
 using IterativeSolvers
 using Test
+using Random
+using SparseArrays
+using LinearAlgebra
 using LinearMaps
 
 @testset "MINRES" begin
@@ -64,4 +67,4 @@ end
     @test hist.isconverged
 end
 
-end
+end