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

We use the testfairy action to upload builds for QA testing, however, the QA team has recently been asking if we can add tags to our builds to make them easier to organize. Unfortunately, the current implementation of TestFairy uploads within fastlane does not support adding tags to builds. Since tags are set via an additional parameter during upload, it seemed like a simple addition to modify the testfairy action to add support. Support for tags was first brought up in discussion #22062.

Description

This PR adds an optional tags parameter when calling the testfairy action to upload a new build. Tags in TestFairy are string labels that aid organization and support categorization of app builds. The tags parameter accepts an array of strings, with a default value of an empty array. The array is joined into a comma separated string, which is required for the TestFairy upload API.

TestFairy documentation on tags

Tested uploading a build in the following scenarios:

• Uploaded a build with no tags
• Uploaded a build with a single tag
• Uploaded a build with multiple tags

All test builds are visible within TestFairy with their respective tags.

Testing Steps

The best way to test these changes is to upload a build to TestFairy containing zero, one, or multiple tags.