gs-plugin-appstream: Fix a crash when no appstream data is found
The xb_silo_query() can return NULL, thus count with it, instead of dereferencing a NULL pointer.
Reported downstream:
https://bugzilla.redhat.com/show_bug.cgi?id=2272028
The xb_silo_query() can return NULL, thus count with it, instead of dereferencing a NULL pointer.
Reported downstream:
https://bugzilla.redhat.com/show_bug.cgi?id=2272028