Wp-calypso: Hosting Config: Show upsell for Personal and Premium plan users

[sixhours]

Steps to reproduce

1. Starting at URL: /hosting-config/[site] on a site with the Free plan. Note the upsell at the top.
2. Visit the same place on a site with a Personal or Premium plan. No upsell, but the page is inaccessible.
3. Look at the same page on a site with a Business or ECommerce plan; the Hosting Configuration settings should be available as expected.

What I expected

Some kind of indication that the Hosting Configuration page is disabled for a reason on non-Personal or Premium plans. An upsell to upgrade to Business to add hosting options.

What happened instead

Personal and Premium plans see a grayed out version of the Hosting Configuration page with no further action or instruction.

[Aurorum]

PR in #41418 for this issue. :)