Signup Popover

[ChristopherChudzicki]

What are the relevant tickets?

Closes https://github.com/mitodl/hq/issues/4591

Description (What does it do?)

Adds a signup popover to

• channel page "Subscribe" button
• Resource card "action" buttons [TODO]

Screenshots (if appropriate):

How can this be tested?

1. Check Cards on homepage, search page, and channel pages:
   • Click the "Add to list" buttons as an authenticated user (staff or otherwise). There should be no changes:
     • Bookmark = "Add to user list"
     • Itemized list = "Add to learning path"
   • As an unauthenticated user, you should only see the bookmark button, and it should open a popover prompting signup.
2. Check "Subscribe" button on channel pages, e.g., http://localhost:8063/c/unit/ocw
   • authenticated users: Subscribe / unsubscribe functions as before
   • unauthenticated users get the popover for signup.
3. http://localhost:6006/?path=/story/smoot-design-popover--basic and the adjacent two popover stories are worht looking at i guess.

[shanbady]

One minor thing i noticed is that the sign up url doesnt appear to redirect to the page that the user left off at (the sign up/log in in the header does)

[shanbady]

Jon has just (a minute ago) merged in a PR that standardizes the value for the site name. probably worth rebasing and integrating that here.

[shanbady]

looks good to merge