Fix warning: cannot map TitleAkas.types "" to a known type

[roskakori]

When running pimdb build, eventually the following warning shows up:

INFO:pimdb:building table title_alias_to_title_alias_type
INFO:pimdb: building mapping from title_alias_type.name to title_alias_type.id
INFO:pimdb: found 8 entries
WARNING:pimdb:cannot map TitleAkas.types "" to a known type: IMDB_TITLE_ALIAS_TYPES should be extended accordingly

Theoretically empty types should already be ignored but apparently for some reason something slips through.

[RealTehreal]

The warning still pops up with the current version of pimdb. Will this somehow affect anything, or can the warning be safely ignored?

[roskakori]

It can be ignored, it just doesn't do anything with the empty data.

But it shouldn't show in the first place. Someone needs to find the energy to dig in and find out where it comes from.