Fix size error in test setup

Author: darsnack

test/convnets.jl

@@ -72,8 +72,9 @@ GC.gc()
 
 @testset "EfficientNet" begin
     @testset "EfficientNet($name)" for name in [:b0, :b1, :b2, :b3, :b4, :b5, :b6, :b7, :b8]
-        xsz = Metalhead.efficientnet_global_configs[name][1]
-        x = rand(Float32, xsz...)
+        # preferred image resolution scaling
+        r = Metalhead.efficientnet_global_configs[name][1]
+        x = rand(Float32, r, r, 3, 1)
         m = EfficientNet(name)
         @test size(m(x)) == (1000, 1)
         if (EfficientNet, name) in PRETRAINED_MODELS