Replace "Vocaloid rankings" list category on TouhouDB

[saturclay]

Is your feature request related to a problem? Please describe. (required)

On TouhouDB, one of the feature songlist types is "Vocaloid ranking".

Describe the solution you'd like. (required)

Instead of "Vocaloid rankings" it should say "Touhou popularity poll", so that I can use it to show the results of the annual popularity poll.

Checklist (required)

Fill out the checklist.

• [x] Searched VocaDB/vocadb for duplicate issues.