Stop hinting the moodlePlugins array

src/org/moodle/ci/Task.groovy

@@ -108,7 +108,7 @@ class Task {
     /**
      * External plugins to install.
      */
-    protected MoodlePlugin[] moodlePlugins = []
+    protected moodlePlugins = []
 
     /**
      * A testsuite to restrict runs to.
@@ -305,7 +305,7 @@ class Task {
      * @param  newPlugin The new plugin to install.
      */
     def addMoodlePlugin(MoodlePlugin newPlugin) {
-        moodlePlugins.add(newPlugin)
+        moodlePlugins << newPlugin
     }
 
     /**