AttachmentGalleryPicker macro WYSIWYG: The buttons in the picker should not be interactable in edit mode

In WYSIWYG edition, the user can interact with the buttons to display attachment on the `Current Page` and `All Pages`, but the picker is completely non functional elsewhere.

For consistency, those buttons should not be interactive in edition mode (or the reverse solution, everything interactive, but this sounds uneeded to me).