Migrate test_tensor.py to TF 2.0

Need to add tf.errors.InvalidArgumentError to errors caused by invalid
shape addition

Author: matthewfeickert

tests/test_tensor.py

@@ -1,6 +1,7 @@
 import pytest
 import logging
 import numpy as np
+import tensorflow as tf
 import pyhf
 from pyhf.simplemodels import hepdata_like
 
@@ -147,13 +148,13 @@ def test_shape(backend):
     assert tb.shape(tb.astensor(0.0)) == tb.shape(tb.astensor([0.0]))
     assert tb.shape(tb.astensor((1.0, 1.0))) == tb.shape(tb.astensor([1.0, 1.0]))
     assert tb.shape(tb.astensor((0.0, 0.0))) == tb.shape(tb.astensor([0.0, 0.0]))
-    with pytest.raises((ValueError, RuntimeError)):
+    with pytest.raises((ValueError, RuntimeError, tf.errors.InvalidArgumentError)):
         _ = tb.astensor([1, 2]) + tb.astensor([3, 4, 5])
-    with pytest.raises((ValueError, RuntimeError)):
+    with pytest.raises((ValueError, RuntimeError, tf.errors.InvalidArgumentError)):
         _ = tb.astensor([1, 2]) - tb.astensor([3, 4, 5])
-    with pytest.raises((ValueError, RuntimeError)):
+    with pytest.raises((ValueError, RuntimeError, tf.errors.InvalidArgumentError)):
         _ = tb.astensor([1, 2]) < tb.astensor([3, 4, 5])
-    with pytest.raises((ValueError, RuntimeError)):
+    with pytest.raises((ValueError, RuntimeError, tf.errors.InvalidArgumentError)):
         _ = tb.astensor([1, 2]) > tb.astensor([3, 4, 5])
     with pytest.raises((ValueError, RuntimeError)):
         tb.conditional(