Fix build tests

Sometimes the build fails with following error:

ERROR:../tests/modules/si-standard-link.c:159:test_si_standard_link_main: assertion failed (wp_object_manager_get_n_objects (om) == 12): (10 == 12)
-------
Summary of Failures:
20/20 test-si-standard-link  FAIL           0.12s (killed by signal 6 SIGABRT)
Ok:                 19  
Expected Fail:      0   
Fail:               1   
Unexpected Pass:    0   
Skipped:            0   
Timeout:            0   

Signed-off-by: Frédéric Danis frederic.danis@collabora.com