test fix

Author: fredrikekre

examples/histogram.jl

@@ -70,7 +70,7 @@ function move(backend, input)
     # TODO replace with adapt(backend, input)
     out = KernelAbstractions.allocate(backend, eltype(input), size(input))
     KernelAbstractions.copyto!(backend, out, input)
-    return
+    return out
 end
 
 @testset "histogram tests" begin