[iOS] Fixed pot duration change crash

Found a new crash, I’m using the new UI - may be related.

Details to reproduce:

  1. Go to ‘Create Pot’
  2. Select ‘Fixed Savings Pot’ and continue to the ‘Select Term Length’ page
  3. Swipe on the month selector, and then quickly scroll in the opposite direction
  4. App Crashes

OS: iOS 12.3
Device: iPhone XS
App Version: v2.46 (523)