Improve database selection logic
Improve database selection logic

This copies over some of the logic from before. We have to match the
previous behavior since we will use this for selecting assemblies as
well now.

RNAcentral/rnacentral-import-pipeline,RNAcentral/rnacentral-import-pipeline,RNAcentral/rnacentral-import-pipeline,RNAcentral/rnacentral-import-pipeline