dm-4748 redirect editors from admin

[PhilipDeFraties]

JIRA issue link

https://agile6.atlassian.net/browse/DM-4748

Description - what does this code do?

• add redirect_editor_from_admin_dashboard method to ApplicationController, call as before_action for activeadmin requests

Testing done - how did you test it/steps on how can another person can test it

1. As a user with a page_group_editor role, try and access the admin dashboard
2. Verify you are redirected to the Community Editor Portal

Screenshots, Gifs, Videos from application (if applicable)

Link to mock-ups/mock ups (image file if you have it) (if applicable)

Acceptance criteria

• [ ]

Definition of done

• Unit tests written (if applicable)
• e2e/accessibility tests written (if applicable)
• Events are logged appropriately
• Documentation has been updated, if applicable
• A link has been provided to the originating JIRA issue
• No sensitive information (i.e. PII/credentials/internal URLs/etc.) is captured in logging, hardcoded, or specs