Create filter to find all incidents assigned to police

**Is your feature request related to a problem? Please describe.**
Can't search for inquiries assigned to police (or any other non EC organization) - in order to follow up and close them

**Describe the solution you'd like**
Add a filter as "assigned to organisation" and "assigned to division" as drop downs.

No file or test is named. Start by locating the existing inquiry search and filter entry point, then trace how assignment organizations and divisions are represented. The work is done when organization and division dropdown filters can find inquiries assigned to police or another non-EC organization for follow-up and closure.

Written by the indexing model from the issue text.