CKAN Inventory DB clear

[jbrown-xentity]

On the CKAN inventory (at least in development environment), the CKAN command for clearing the database crashes the command console and never finishes. No error logs are noted.

How to reproduce

1. Pull and run make up-with-data for the inventory
2. Get onto the app docker image: docker-compose exec app /bin/bash
3. Run /usr/lib/ckan/bin/paster --plugin=ckan db clean

Expected behavior

CKAN DB should be cleared of all relevant data (the command /usr/lib/ckan/bin/paster --plugin=ckan db init would need to be run to re-initialize the DB structure)

Actual behavior

Command never ends/releases, DB is left in an unworkable state.

[adborden]

I wonder if this is related to #961 and the version of psycopg2 installed.