Explore PROJECTS_ROOT and PROJECT_SOURCE env vars with devfile team

Problem

At present, the devfile processor in rails use PROJECTS_ROOT as the entrypoint for mounting and storing user data. However, the full implications of these env vars are not clear and what they mean for spawned workspaces across their lifecycle

Solution

• Explore the implications of these env vars and how they affect workspaces across their lifecycle
• If required, introduce changes to better conform to the devfile specifications wrt these env vars