Update cupy xfails

Author: asmeurer

cupy-xfails.txt

@@ -36,6 +36,7 @@ array_api_tests/test_linalg.py::test_svdvals
 array_api_tests/test_linalg.py::test_trace
 # We cannot modify array methods
 array_api_tests/test_operators_and_elementwise_functions.py::test_divide[__truediv__(x, s)]
+array_api_tests/test_operators_and_elementwise_functions.py::test_floor_divide[__floordiv__(x, s)]
 array_api_tests/test_operators_and_elementwise_functions.py::test_remainder[__mod__(x1, x2)]
 array_api_tests/test_operators_and_elementwise_functions.py::test_remainder[__imod__(x1, x2)]
 array_api_tests/test_operators_and_elementwise_functions.py::test_remainder[__mod__(x, s)]