buildType property
BuildType is how a git app builds: pack, the zero-config default that detects the project, or dockerfile. An image app carries image, which means it never builds.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
String? buildType;