Change the default iPhone 14 Pro/Pro Max frame colors from PURPLE to BLACK.

[michaellenaghan]

Checklist

• I've run bundle exec rspec from the root directory to see all new and existing tests pass
• I've followed the fastlane code style and run bundle exec rubocop -a to ensure the code style is valid
• I see several green ci/circleci builds in the "All checks have passed" section of my PR (connect CircleCI to GitHub if not)
• I've read the Contribution Guidelines
• I've updated the documentation if necessary.
• I've added or updated relevant unit tests.

Motivation and Context

iPhone 14 Pro and Pro Max frames were added in Jan. Unfortunately, the default frame color — used when the requested color isn't available — is PURPLE. If you look at the other default colors in the file you'll see that PURPLE is a highly atypical choice.

Description

This changes the default color to BLACK.