Fix ORKTextChoiceOther.choice not working on iOS 14

[marius-serban]

Fixes issue #1406 by setting up the subviews of a ORKChoiceViewCell as children of contentView rather than the cell directly.

Tested on both iOS 14 and iOS 13.

[scdi]

Thank you for the fix. I think that it is a partial fix. It works for single choice item but not for multiple choice item.
When used with multiple choice items, the other selected choices get deselected.

[scdi]

@jscubida Do you have a demonstration where the fix works for multipleChoice formStep. It seems that "other choice" deselect all other choices.

[marius-serban]

@scdi I think it'd be better to raise a separate issue for the multiple choice problem. This PR focuses on only fixing #1406 as it was described.

It seems that the ORKTextChoiceOther.choice is working in iOS 13 but NOT with iOS 14.
A click in the TextBox that opened when the other choice is selected closes the TextBox rather than allowing the user to enter a text.

I think that raising it as a separate issue will increase its chances of getting fixed. I don't have the capacity to look into it, but others might.

[scdi]

Thank you for your work on this. I am sorry that the problem submitted cannot be fixed at this time. The example shown above, submitted in December, last year, is about the ORKChoice not working for multipleChoice formStep.

[jsubida]

@scdi I think the behavior you illustrated is due to the value for exclusive:. If you have the code that was run to produce the GIF above, I can take a look. Regardless, I have a sample project here that allows you to view the difference in behavior when exclusive: is true or false. Would this suffice or were you looking for something else?

[scdi]

@jscubida, You are a life saver. I have needed for so long to use this functionality and could not. You are right, the exclusive:. should be false for the Other to work when .multipleChoice is being used. Thank you so much.