Themes in OSS project repos are out of sync with docs repo layout changes

[jputrino]

Describe the bug

In the docs repo, I made a number of updates that addressed the new model of building multiple product documentation sets together. These changes are only in the docs repo.

I noticed today that the content shipping from the docs repo has the breadcrumb on the landing page, while the OSS projects do not.

Expected behavior

Actual behavior