merge method
Implementation
Swagger merge(Swagger other) {
final _tags = List<SwaggerTag>.from(tags)..addAll(other.tags);
final _servers = List<SwaggerServer>.from(servers)..addAll(other.servers);
return copyWith(
paths: other.paths,
tags: _tags.toSet().toList(),
servers: _servers.toSet().toList(),
);
}