SalutConnection: Fix a leak: call tp_contacts_mixin_finalize()
SalutConnection: Fix a leak: call tp_contacts_mixin_finalize()

freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut,freedesktop-unofficial-mirror/telepathy__telepathy-salut