Fix collection item button appearence

[11ya]

Fix collection button appearence for adding items, when collection label is false

[11ya]

I put button into empty label for consistency with form_label block

[phiamo]

@isometriks what do you thik, actually its a good fallback solution, and setting label to false shoudl not necessarly need to lead to misisng button

[isometriks]

So this just puts it next to the widget if there's no label? Seems fine to me also