make_and_add_image(): prevent hash conflict in rare cases

Include all parameters in hash calculation to prevent misbehavior

- CAA can have same data for 2 or more images (ie. same image uploaded twice with different types)
- adding few strings to hash calculation doesn't cost much
- results in case of cache key conflict are very unpredictable

See https://github.com/musicbrainz/picard/pull/232#discussion_r12419523