Updated iOS shell app for SDK 38 with fixed integer tagging in expo-g…

…l for iOS 14.

[ ] I've read the Contribution Guidelines.
[x] I've updated the CHANGELOG if necessary.
[ ] I've ensured the unit and smoke tests are still passing - either by running yarn test:unit and yarn test:smoke:[ios|android] or by checking the appropriate CircleCI builds' statuses.
[ ] I've manually tested whether the changes I made work as expected.

expo / turtle