Make device OAuth flow authorization pages consistent with regular OAuth authorization page

Summary

Brings the two device authorization grant views (index.html.haml and authorize.html.haml) in line with the regular OAuth authorization page (doorkeeper/authorizations/new.html.haml), and fixes a bug where the confirmation page received no application or scope data.

Part of UI FR for Verbose OAuth Application information (#539182 - closed)

Screenshots

authorize.html.haml — device confirmation

Before	After

References

• b33cfbc4 — Add doorkeeper device auth support: the original commit that introduced the device authorization grant views
• e02da7cb — Add delay to when pointer events are enabled for OAuth authorize page: introduced the #container + gl-pointer-events-none pattern applied here
• 74620473 — Remove id attribute from OAuth form: security hardening that the device views should stay consistent with