Use Gem.ruby_api_version for GEM_HOME

[aramprice]

• do not add $GEM_HOME/bin to $PATH

[Copilot]

Pull request overview

Updates the CI template used to generate src/compile-*.env so that bosh_generate_runtime_env sets GEM_HOME using Ruby’s API version (instead of the patch version) and avoids adding $GEM_HOME/bin to PATH, aligning the generated runtime environment with how Bundler lays out gems.

Changes:

• Compute GEM_HOME using Gem.ruby_api_version rather than <ruby_patch_version>.
• Stop appending $GEM_HOME/bin to PATH in the generated runtime.env.
• Add quoting around exported environment values in the heredoc output.

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