Logo and button link to dashboard

[jonkafton]

What are the relevant tickets?

Closes: https://github.com/mitodl/hq/issues/8976

Description (What does it do?)

• The "MIT Learn" header logo links to /dashboard when a user is logged in
• A button link to the Dashboard is shown on desktop when a user is logged in and not in a dashboard page.
• The header mobile breakpoint is increased to 900px to accommodate the button and to fix a layout bug in Prod in which space is limited even without the additional button.

Screenshots (if appropriate):

Layout bug at 600px to ~700px:
Before:

After:

How can this be tested?

When not logged in:

• Check that MIT Learn header link points to the homepage, /.

When logged in:

• Check that MIT Learn header link points to your dashboard, /dashboard.
  • When not on a dashboard page:
    • Check that the new dashboard button shows in the header (desktop only).
  • When on a dashboard page:
    • Check that the dashboard button does not show.

Additional Context

[abeglova]

LGTM except for the stray logging statement

[abeglova]

You forgot to remove console.log here

[abeglova]

Surprised that this did not break the tests

[jonkafton]

We can add an ESLint rule. Problem is we can't build with lint errors, so catch 22 for debugging production builds.