Outputting a catalog of the stores written

[jbusecke]

#9 is producing actual useable output! While I will wait with merging that until the dependencies are merged/cleaned I need to get the data into the hands of the users like @Timh37.

We currently have a non-public BQ database that contains the instance_id and the store name. It should be easy enough to write a gh action that reads the table and produces a csv (for now, to ensure backwards consistency with the existing catalog).

[jbusecke]

Closed via #9