Skip ctypes test

Author: msimacek

graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_memoryview.txt

@@ -86,5 +86,6 @@
 *graalpython.lib-python.3.test.test_memoryview.BytesMemoryviewTest.test_weakref
 *graalpython.lib-python.3.test.test_memoryview.BytesMemoryviewTest.test_writable_readonly
 *graalpython.lib-python.3.test.test_memoryview.OtherTest.test_copy
+*graalpython.lib-python.3.test.test_memoryview.OtherTest.test_ctypes_cast
 *graalpython.lib-python.3.test.test_memoryview.OtherTest.test_memoryview_hex
 *graalpython.lib-python.3.test.test_memoryview.OtherTest.test_pickle

graalpython/lib-python/3/test/test_memoryview.py

@@ -515,6 +515,7 @@ class ArrayMemorySliceSliceTest(unittest.TestCase,
 
 
 class OtherTest(unittest.TestCase):
+    @test.support.impl_detail("ctypes", graalvm=False)
     def test_ctypes_cast(self):
         # Issue 15944: Allow all source formats when casting to bytes.
         ctypes = test.support.import_module("ctypes")