[Flanker]The app crashes is the user doesn't give an answers

[MaksimYurys]

Preconditions: The user is logged into the mobile The user has an applet with the "Simple & Choice Reaction Time Task Builder" activity

Steps to reproduce:

1. Launch the "Simple & Choice Reaction Time Task Builder" activity
2. Don't give answers
3. Pay attention to the screen

Actual result: The app crashes is the user doesn't give an answers

Expected result: The app doesn't crash if the user doesn't give an answers

Video: https://images.zenhubusercontent.com/103405139/8d9a2745-ceab-4623-af5f-6ea27ee33ad8/18a647a0_2278_4656_b8d6_bb849b3394dc.mp4

Environment: MindLogger Pilot v0.21.48 prod iPhone 8 // 14.7.1

[natalia-muzyka]

url to create flanker applet: https://raw.githubusercontent.com/ChildMindInstitute/mindlogger-flanker-applet/master/protocols/flanker/flanker_schema

video (how to create): https://www.screencast.com/t/kCZeWUkGLZy0

account with activities: flanker_test@mail.com / 123456 config flanker v5, v6

[yzenchanka]

Verified as fixed. The app doesn't crash if the user doesn't give an answers Environment: Mobile app version 0.21.59 iPhone 7 Plus / iOS 14.4 iPad 7 Gen / iOS 15.4.1 account with activities: flanker_test@mail.com / 123456 config flanker v5, v6

[natalia-muzyka]

Verified as fixed.

Environment: Mobile app version 0.21.59 iPhone 7 // iOS 13.1.1 iPhone 13 // iOS 15.6 staging account: flanker_special@ml.com / 123456 Flanker_360, Config Flanker (both activities)