Add read only mode to seeds

[pgwillia]

Describe the bug
ReadOnlyMode.create(enabled: false) should be added to the seeds. It's in a migration but that doesn't get set in development if you're running db:prepare or db:setup.

To Reproduce
Steps to reproduce the behavior:

1. docker-compose down -v
2. docker-compose up -d
3. rails db:prepare (as per the README)
4. See error

Expected behavior
The seeds will prepare the database for development without extra steps.

Additional context
This is where it's added in a migration

jupiter/db/migrate/20200831182732_add_initial_read_only_modes.rb

Lines 1 to 5 in 087a261

	class AddInitialReadOnlyModes < ActiveRecord::Migration[6.0]
	def change
	ReadOnlyMode.create(enabled: false)
	end
	end