fix(dynamic-links): fix crash when building dynamic link with no internet

[russellwheatley]

Description

Codec wasn't able to parse NSUrl & NSError which was causing app to crash. I've removed them from the details object sent back to Flutter as they aren't used.

The error message has also been replaced. An unknown error has occurred for the more helpful The request timed out which is already a description in the underlying native error.

Related Issues

fixes #7911

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