fix (parse-service) options in result must be string

Author: vengrov

lib/server-code/runners/tasks/parse-service.js

@@ -33,8 +33,8 @@ function parseService(task) {
       // version       : service.version,
       // description   : service.description,
       config: service.configItems.map(item => Object.assign({
-        //TODO: server bug workaround
-        ___jsonclass: 'com.backendless.marketplace.model.BlConfigurationItemDescription'
+        ___jsonclass: 'com.backendless.marketplace.model.BlConfigurationItemDescription',
+        options: item.options && item.options.join(',')
       }, item)),
       xml   : service.xml()
     };