Add "beta" label and text to new Libraries tab on Studio Home

[jmakowski1123]

The new Libraries tab should have a "beta" label next to it.

Note that the same (or similar) "beta" label should appear on the course side, on the new Library Content block/tile on the Unit Page. Noting here for design consistency, requirements here: https://github.com/orgs/openedx/projects/66/views/1?pane=issue&itemId=80800183

The text underneath the "beta" label should read:

Welcome to the new Beta Libraries experience! Libraries have been redesigned from the ground up, making it much easier to reuse and remix course content. The new Libraries space lets you create, organize and manage new content; reuse your content in as many courses as you'd like; sync updates centrally; and create and randomize problem sets. See here [placeholder url] for a tutorial.

[bradenmacdonald]

@jmakowski1123 I think we need this for Sumac, so it should be done in an earlier epic than 6?

[jmakowski1123]

@jmakowski1123 I think we need this for Sumac, so it should be done in an earlier epic than 6?

We discussed - all of the stories in Epic 6 will be covered for Sumac. We'll punt epic 8 to Teak.