fix(ios): force layout of view when changing the safe area insets

[edusperoni]

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• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/CONTRIBUTING.md#commit-messages.
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What is the current behavior?

if the safeareainsets change, the children view's safeareainsets are not updated and will layout wrongly

What is the new behavior?

forces the layout before layouting the children