Allow default values null and undefined to prevent validation errors

[helenaford]

Not allowing null or undefined values can cause unexpected validation errors during runtime, and causes code like this:

delete notification.ios.field

[helenaford]

Need to update all optional props with | undefined and validation to allow for it since ts update.

[github-actions]

Hello 👋, to help manage issues we automatically close stale issues.

This issue has been automatically marked as stale because it has not had activity for quite some time.Has this issue been fixed, or does it still require attention?

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