Pin numpy<=1.19.5 in requirement_dev (#689)

* test

* Deprecate python 3.5 CI (update to 3.6) (#686)

Author: jiafatom

requirements-dev.txt

@@ -1,3 +1,4 @@
+numpy<=1.19.5
 pillow
 pytest
 onnxruntime

tests/test_layers.py

@@ -2387,7 +2387,7 @@ def test_masking(runner, rnn_class):
     onnx_model = keras2onnx.convert_keras(model, model.name)
     x = np.random.uniform(100, 999, size=(2, 3, 5)).astype(np.float32)
     expected = model.predict(x)
-    assert runner(onnx_model.graph.name, onnx_model, x, expected)
+    assert runner(onnx_model.graph.name, onnx_model, x, expected, rtol=5e-3)
 
 
 @pytest.mark.parametrize("rnn_class", RNN_CLASSES)