[match] Fixes missing job-token error in GitLab storage mode

[darbyfrey]

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

This PR fixes the error reported in #21018 (comment) related to the GitLab Secure Files Fastlane Match storage backend.

Description

The error was introduced in this change #21018 which added an additional configuration keys check that didn't exist before. This issue is resolved by adding the optional configuration keys to the global configuration object so that the keys can be validated correctly.

Testing Steps

Tested locally and added automated tests.

[darbyfrey]

@getaaron @joshdholtz this PR fixes #21018 (comment), could you take a look when you have a moment? Thanks!

[joshdholtz]

Thanks for fixing! 🙌