Update product integration documents for how to run sandbox pipeline with full Big Bang integration

Looking to add content into https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/docs/developer/package-integration/package-integration-pipeline.md#big-bang-pipeline. This should cover:

• What does one need to do to make the Big Bang integration pipeline run in Sandbox?
• What are some common issues you may come across (e.g. BB names your resources differently because of flux)
• How to handle the Git repo pointing to a branch and then merging into main and the branch is no longer.
• How do I turn on or off Big Bang packages?
• Reference to how to turn on or off pipeline stages if needed (e.g. SKIP UPGRADE)