Avoid transients in test_itertools

Author: msimacek

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

@@ -1411,6 +1411,9 @@ def test_islice(self):
         it = islice(it, 1)
         self.assertIsNotNone(wr())
         list(it) # exhaust the iterator
+        # GraalPy change: avoid transients
+        if sys.implementation == 'graalpy':
+            return
         support.gc_collect()
         self.assertIsNone(wr())