[Breadcrumbs]: package name is inconsistent

[GarthDB]

Description

Breadcrumbs:

• On the design system website, it is breadcrumbs
• On the CSS website, the title says breadcrumbs

Breadcrumb:

• The npm package is breadcrumb.
• The URL on the CSS website is spectrum-css/breadcrumb.html.

I would recommend changing it to breadcrumbs as that follows the design system website and fits with similar patterns like tabs.

[GarthDB]

The annoying part of renaming it would be a brand new package and deprecating the old package for just a single letter.

[castastrophe]

Hmm the classname is Breadcrumbs with an S too. @pfulton what would you think of a package rename?