Speed up quantized model tests.

Author: datumbox

test/expect/ModelTester.test_resnet18_quantized_expect.pkl

@@ -803,7 +803,7 @@ def test_quantized_classification_model(model_fn):
     set_rng_seed(0)
     defaults = {
         "num_classes": 5,
-        "input_shape": (1, 3, 224, 224),
+        "input_shape": (1, 3, 64, 64),
         "pretrained": False,
         "quantize": True,
     }