"Add content" links should be styled as inline buttons

@thomas.frobieter could you please add style for the add content buttons in dashboard?
I repaired the menu. I think a button style with inline buttons would make sense, because in projects these can be around ~10-15 buttons? Oerhaps with a plus or something like that?

I already installed the fix in D10 and D11 template.

@thomas.frobieter if possible could you do that? Should be a quick win and is especially helpful if there are several content types. For example see our template or z m p