Soft Delete a Collection

[pomegranited]

Update the Authoring MFE to use the REST APIs implemented by openedx/modular-learning#231:

• Add "Delete Collection" to a collection card's ⋮ menu
• Clicking "Delete Collection" raises a confirmation modal.
• When delete is confirmed, call the "Soft Delete Collection" REST API
• Show an "Undo Toast" that calls the "Re-enable Collection" REST API

[navinkarkera]

@jmakowski1123 @lizc577 @sdaitzman @marcotuts This is ready for AC testing on the sandbox

[jmakowski1123]

Looks good!