PeopleInSpace uses [Build Sources](https://docs.gradle.org/current/userguide/organizing_gradle_projects.html#sec:build_sources) (`buildSrc`). Is there a reason why [Composite Builds](https://docs.gradle.org/current/userguide/composite_builds.html) is not used instead? As I was checking how PeopleInSpace manages versioning, I saw this PR https://github.com/joreilly/PeopleInSpace/pull/116 and it prompted me to look into buildSrc and Composite Build.