medialibrary: assertion during run_vlc.sh test

[00007b5ed4000ea0] idummy access: command `nop'
vlc: ../../src/misc/medialibrary.c:124: libvlc_MlRelease: Assertion `vlc_list_is_empty( &p_ml->cbs )' failed.
../test/run_vlc.sh: line 15: 718425 Aborted                 (core dumped) $VLC --play-and-exit vlc://nop
FAIL test/run_vlc.sh (exit status: 134)

changed milestone to %4.0

added Component::Media Library Component::Test Type::bug labels

Hello, I can't reproduce it with an up-to-date master using medialibrary from the contrib.