Test: rollup node can play refutation over a protocol migration

Several cases to test depending on in which protocol these events appear: conflicting commitment, conflicting inbox/tick, game started:

• event	protocol
  conflicting commitment	previous
  inbox/tick	previous
  game started	previous

• event	protocol
  conflicting commitment	previous
  inbox/tick	previous
  game started	current

• event	protocol
  conflicting commitment	previous
  inbox/tick	current
  game started	current