Loading and auto-saving an edited code component

When I try to publish this, I get an error from the publish endpoint

'This value should not be blank'

Here's the detail

  "detail": "This value should not be blank.",
  "source": {
    "pointer": "name"
  },
  "meta": {
    "entity_type": "js_component",
    "entity_id": "garry",
    "label": "Garry",
    "autosave_key": "js_component:garry"
  }
}

Will try to fix it

The name is indeed blank

Creating a new component

1) Name is sent

2) Create another component

2) GET request starts but is aborted

3) PATCH request runs but sends the value of name

4) Name is now set to old value

I think the same thing is occurring with a clean state - but instead of sending the old component name, it is sending an empty value.

I think we can fix this in the 'create component' dialog, going to try that

The issue isn't coming from the add dialog, its from the code added here.
Because we save an autosave entry before we get data from the backend, we are relying on the name from code editor slice.
This is empty if the component is new and the first component created here.
It is the name of the previously edited component if not the first one.

I think this highlights the brittleness of the 204 from the backend and we should reconsider a 307 so that the fetch always gets some data.

Actually, ignore #13 - I was able to resolve this from the add dialog.
I'll add a test.

Fixed #11 and #12 and added a test

There's a couple of open comments on the MR but other than that I think this is RTBC