Forced close of design sections when clicking "Change theme" link
Forced close of design sections when clicking "Change theme" link

refs https://github.com/TryGhost/Admin/commit/f9a2626ae445da4647718b84585d156ca11bdbb4

- nav menu felt inconsistent where clicking a section nav item closes all other sections but clicking the change-theme nav item didn't

TryGhost/Ghost,TryGhost/Ghost,TryGhost/Ghost