[WifiSetup] Swap buttons position in Skip dialog

According to material-spec, buttons that keep users in the same
screen should be on the left (negative button) while button that
intorduce changes should be on the right, even if the action is
destructive.

Bug: 18542108
Change-Id: I335f83c6bb810cd43aeda28566baacea39435c57
1 file changed