[deliver] read values from SharedValues context only if needed

[rogerluan]

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

Resolves #17593

Description

Code is pretty straight forward, the values were being overridden by the shared values context instead of using a ||= operator (i.e. "assign if needed").

Testing Steps

This PR was tested against the test case described in #17593.

To test this branch, modify your Gemfile as:

gem "fastlane", :git => "https://github.com/fastlane/fastlane.git", :branch => "rogerluan-prefer-deliver-inline-option"

[stocc]

Hi, thanks for the fix!
Happy to report it works great, also in my main Fastfile 🎉

[joshdholtz]

Oh my goodness! I can't believe it wasn't already like this 😱 Thanks for catching this! Really appreciate the contribution ❤️

[fastlane-bot]

Congratulations! 🎉 This was released as part of fastlane 2.168.0 🚀