libtracker-extract: Lookup rules after maybe initializing in get_fallback_rdf_types()
libtracker-extract: Lookup rules after maybe initializing in get_fallback_rdf_types()

Otherwise the first lookup might come up empty.

outofbits/tracker,outofbits/tracker,outofbits/tracker,outofbits/tracker,hoheinzollern/tracker,hoheinzollern/tracker,outofbits/tracker,hoheinzollern/tracker,outofbits/tracker,outofbits/tracker,hoheinzollern/tracker,hoheinzollern/tracker,hoheinzollern/tracker,hoheinzollern/tracker