Fix cannot override Create and Edit buttons style with a theme

[IAmVisco]

Closes #8623

[fzaninotto]

tests fail

[IAmVisco]

Yeah I noticed and running 'em locally to check atm👍

[IAmVisco]

@fzaninotto could you approve the workflows again please?

[fzaninotto]

Thanks!

[slax57]

@davidhenley Nope, we are not aware of such a bug.
I just had a look at the simple example stackblitz but I see nothing wrong there.
If you manage to reproduce in this example, feel free to open a new issue!

[davidhenley]

Hey @slax57 I figured it out. I had something in the theme overrides that I guess just started "working" (failing) with this commit.

RaCreateButton: {
  styleOverrides: {
    root: {
      display: 'none'
    }
  }
}