[trainer] Fix reports failure with skipped tests

[tahirmt]

Trainer would fail if there are any skipped tests in case of retries.

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've read the Contribution Guidelines
• I've updated the documentation if necessary.

Motivation and Context

Noticed that when using trainer with retried tests, it would fail the action even when the end result with retries is success. Using number_of_failures_excluding_retries to fix the issue.

I think the issue is the same as this. Resolves #19687

Description

Changed the check for tests_successful for trainer test_parser` to use number of failures excluding retries

Testing Steps

Use trainer on an xcresult file that includes retries but with an overall successful result with fail_build set to tree and expect trainer to succeed.

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[tahirmt]

I'm sorry for the force push but I committed with the wrong email address and couldn't sign the CLA without it.

[joshdholtz]

This makes so much sense! Thank you for catching and fixing ❤️

[fastlane-bot]

Congratulations! 🎉 This was released as part of fastlane 2.205.1 🚀