Fix a bug in the is_integer_dtype() helper function

Author: asmeurer

array_api_tests/array_helpers.py

@@ -301,7 +301,7 @@ def assert_same_sign(x, y):
 def is_integer_dtype(dtype):
     if dtype is None:
         return False
-    return dtype in [int8, int16, int32, int16, uint8, uint16, uint32, uint64]
+    return dtype in [int8, int16, int32, int64, uint8, uint16, uint32, uint64]
 
 def is_float_dtype(dtype):
     if dtype is None: