fix oldroydb test skip

10 jobs for oldroydb in 49 minutes and 9 seconds (queued for 2 seconds)
Name Stage Failure
minimal-windows Test
36.86s call     lbmpy_tests/full_scenarios/schaefer_turek/
35.41s call lbmpy_tests/[Stencil.D3Q15-polynomial]
32.68s call lbmpy_tests/[setup1]
32.33s call lbmpy_tests/[Stencil.D3Q15-monomial]
=========================== short test summary info ===========================
FAILED lbmpy_tests/full_scenarios/square_channel/
====== 1 failed, 564 passed, 25 skipped, 4 warnings in 902.16s (0:15:02) ======
Cleaning up project directory and file based variables
ERROR: Job failed: Process exited with status 1