Update Dockerfile
Update Dockerfile

Seems that the base of the Dockerfile has changed. This updates things
to use the latest correct versions. Additionally, it uses the pgloader
that is present in Debian now.

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