test_roundtrip fails after python update

[vcunat]

Since python: 3.13.7 -> 3.13.8 we get this test error all the time:

FAILED test/test_sparql/test_translate_algebra.py::test_roundtrip[test_other__service1] - TypeError: object of type 'Suppress' has no len()
= 1 failed, 7229 passed, 61 skipped, 372 deselected, 329 xfailed, 36 xpassed, 4825 warnings in 44.20s =

You can get an example full log at https://cache.nixos.org/log/jdhbgzc7s26ash83lzrjm9hkydnxzgv3-python3.13-rdflib-7.1.4.drv
I tried with 7.2.1 as well, but it looked the same.

[WhiteGobo]

That test is currently expected to fail with recursion error instead of the type error. We could get rid of the error by removing the raises restriction on xfail

[WhiteGobo]

Here a pr so that pytest now succeeds again, but i couldnt test it, because i have no python 3.13.8 installed.