Fix design for loading of link suggestions

[vraja-pro]

We have updated the design for the notice of unindexed notice for the link suggestion to unify the style across sidebar, iframe and elementor, and in dark themes, regular themes:

The loading message for the link suggestion should also be updated and that will solve the striping of the css in block based theme:
Block based theme:

Regular dark theme:

Regular theme:

@ux-tom @uxkai