Skip test relying on random generator

Author: msimacek

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

@@ -780,7 +780,11 @@ def b():
 
 >>> import random
 >>> gen = random.Random(42)
->>> while 1:
+
+
+# XXX Truffle change: our random generator generates different numbers
+@support.impl_detail(graalvm=False)
+>>> while 1: # doctest: +SKIP
 ...     for s in sets:
 ...         print(" %s->%s" % (s, s.find()), end='')
 ...     print()