chore: update missing localization strings for face not prepared reasons

[phantumcode]

Issue #, if available:
#76

Description of changes:

• Add localization string for FaceNotPreparedReason string values

Check points: (check or cross out if not relevant)

• Added new tests to cover change, if needed
• Build succeeds with all target using Swift Package Manager
• All unit tests pass
• Security oriented best practices and standards are followed (e.g. using input sanitization, principle of least privilege, etc)
• Documentation update for the change if required
• PR title conforms to conventional commit style
• If breaking change, documentation/changelog update with migration instructions

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.