batches: temporarily disable namespace selector
Created by: courier-new
Closes https://github.com/sourcegraph/sourcegraph/issues/37135.
Just comments out code related to the namespace selector and adds TODO notes with instructions for how to restore. Creating a batch change from the user or org list page will also both temporarily point to the default create page, since the user- and org-specific create pages pre-select a different namespace.
Test plan
Manually tested that creating a batch change uses the user namespace only. Form has storybook coverage as well and should report a diff to Chromatic.
App preview:
Check out the client app preview documentation to learn more.