[image_picker_ios] requestFullMetadata property miss converting NSNumber to Bool

[codingiran]

In Objective-C, NSNumber should convert to Bool manually by type conversion, otherwise nonnull NSNumber will always convert to "YES".

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie or stuartmorgan on the #hackers channel in Chat (don't just cc them here, they won't see it! Use Discord!).

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[stuartmorgan-g]

Thanks for the contribution! You’ve checked boxes in the PR checklist above that are not reflected in this PR, so I’m assuming this is a work in progress and am marking it as a Draft. Please review the checklist, updating the PR as appropriate, and when the checklist reflects the state of the PR as posted please feel free to mark it as ready for review.

[stuartmorgan-g]

Closing as obsolete due to #5266