Remove param based onboarding navigation

[jonkafton]

What are the relevant tickets?

Closes https://github.com/mitodl/hq/issues/7223

Description (What does it do?)

Removes the onboarding finish navigation configurable by a next param on the querystring as we always want to go to the dashboard screen.

Previously the backend /login and onboarding handling looked like:

• A user on e.g. the topic page hits "Log in" and requests /learn/login?next=https://learn.mit.edu/topics
• The login handler determines whether they have completed onboarding
• If yes:
  • User redirected to https://learn.mit.edu/topics
• If no:
  • User redirected to https://learn.mit.edu/onboarding?next=https://learn.mit.edu/topics
  • User completes onboarding
  • User is redirected in the frontend to https://learn.mit.edu/topics when they hit "Finish" at the end of onboarding.

We instead want the user to always go to the dashboard when they complete the onboarding, irrespective of their starting point prior to login.

How can this be tested?

The "Log In" button always links to the login endpoint with the current address as set on a next param. Starting from any page as a user that has not completed onboarding (manually set user.profile.completed_onboarding to False):

• Log in.
• Step through onboarding and hit "Finish".
• Confirm that you are on the dashboard page at /dashboard.

[github-actions]

OpenAPI Changes

Show/hide No detectable change.

[github-actions]

OpenAPI Changes

Show/hide No detectable change.

[github-actions]

OpenAPI Changes

Show/hide No detectable change.

[github-actions]

OpenAPI Changes

Show/hide No detectable change.

[shanbady]

works as intended 👍 . only comment is that it feels like we are removing functionality that may need to come back at some point but we can address that when it does

[jonkafton]

works as intended 👍 . only comment is that it feels like we are removing functionality that may need to come back at some point but we can address that when it does

I agree, though perhaps while we have the special case that a user is not onboarded and redirected to the onboarding, we end up with a login redirect to a redirect to the onboarding redirect, to a reroute back to their starting point. As I understand it, the starting point is invalidated by the initial redirect to onboarding.