Deleted the continue button from adjustment index

On the adjustment index (in the admin) was a continue button.
The button only shows up on this page, it's a leftover from the old 'manual add an order' proces in the admin.

I deleted it.

Fixes #5395
Regression spec for 'stack level too deep' #5384

Fixes #5384
Add in fix from @andrzejpolis Fixes #5384 Fixes #5386