[fastlane_core] add pods project schemes environment variable

[tejassharma96]

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

At my workplace for one of our projects, we run a test spec from one of our internal cocoapods as a smoke test before running lengthier UI tests that depend on that pod. I was able to use the cocoapods post_install block to make the scheme public when installing on CI, but we're still unable to run those tests on fastlane since fastlane filters out pods schemes.

Description

I added an environment variable to optionally disable the filtering out of environment variables.
I tested this out by verifying that the scheme could be found with the environment set to a truthy value, and it could not be found when the environment variable is unset or set to a falsy value.

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[tejassharma96]

@googlebot I signed it!

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[joshdholtz]

This makes sense to me! Sorry if this caused any issues but thank you for fixing 😊

[tejassharma96]

Thanks for the quick merge!

[fastlane-bot]

Hey @tejassharma96 👋

Thank you for your contribution to fastlane and congrats on getting this pull request merged 🎉
The code change now lives in the master branch, however it wasn't released to RubyGems yet.
We usually ship about once a week, and your PR will be included in the next one.

Please let us know if this change requires an immediate release by adding a comment here 👍
We'll notify you once we shipped a new release with your changes 🚀

[fastlane-bot]

Congratulations! 🎉 This was released as part of fastlane 2.185.1 🚀