TST: Remove xfail from test after pylib release

tests/test_error_stuff.py

@@ -342,7 +342,6 @@ def test_update_acl_errors():
     assert te.value.has_error(AmbiguousEntityError)
 
 
-@pytest.mark.xfail(reason="Waiting for pylib release")
 def test_URI_too_long():
     """Some tests for variours URI too long commands.