toJson method
Converts the publisher job to JSON representation.
Returns a Map<String, dynamic> containing only the publisher
configurations that are present (non-null).
Implementation
Map<String, dynamic> toJson() => {
if (fastlane != null) "fastlane": fastlane?.toJson(),
if (firebase != null) "firebase": firebase?.toJson(),
if (xcrun != null) "xcrun": xcrun?.toJson(),
if (github != null) "github": github?.toJson(),
};