ci: add BYO_GIT checkbox to the Deploy APL action

[j-zimnowoda]

📌 Summary

This pull request adds support for a "Bring Your Own Git" (BYO_GIT) integration to the integration.yml GitHub Actions workflow. The main changes introduce a new input flag, validate required secrets, and pass these secrets to relevant jobs for use during installation.

Key changes:

BYO_GIT input and validation:

• Added a new boolean input BYO_GIT to the workflow, allowing users to enable the BYO Git integration option.
• Added a step to validate that required secrets (BYO_GIT_PAT and BYO_GIT_URL) are set if BYO_GIT is enabled, failing early if they are missing.

Secrets management and usage:

• Passed BYO_GIT_PAT and BYO_GIT_URL secrets to the relevant job environments to make them available during workflow execution.
• Updated the installation command to use the BYO Git repository URL, password, and branch (based on the domain) when the BYO_GIT option is enabled.

🔍 Reviewer Notes

🧹 Checklist

• Code is readable, maintainable, and robust.
• Unit tests added/updated

[Copilot]

Pull request overview

This PR updates the “Deploy APL” GitHub Actions workflow to optionally configure APL to use a predefined external Git repository for its values repo (“BYO_GIT”), controlled via a new workflow_dispatch checkbox. It adds secret validation and conditionally injects otomi.git.* Helm values during install when enabled.

Changes:

• Add a BYO_GIT boolean input to the workflow_dispatch form.
• Validate BYO_GIT_PAT / BYO_GIT_URL secrets when BYO_GIT is enabled.
• When enabled, pass otomi.git.repoUrl, otomi.git.password, and otomi.git.branch into the APL install command.