fix links

docs/modules/ROOT/partials/source-structure-link.adoc

@@ -1 +1 @@
-For a detailed description of the separate jar files see <<getting-started/jme3_source_structure.adoc#structure-of-jmonkeyengine3-jars,this list>>.
+For a detailed description of the separate jar files see <<ROOT:getting-started/jme3_source_structure.adoc#structure-of-jmonkeyengine3-jars,this list>>.

docs/modules/tutorials/pages/beginner/hello_collision.adoc

@@ -268,7 +268,7 @@ As usual, you initialize the game in the `simpleInitApp()` method.
 
 Currently, jMonkeyEngine has two versions of link:https://pybullet.org/wordpress/[Bullet Physics]. A java port, link:http://jbullet.advel.cz/[jBullet], and link:https://en.wikipedia.org/wiki/Java_Native_Interface[JNI] (native) implementation. Although both accomplish the same goal of adding physics to your game, how you interact with each is quite different. This tutorial and it's examples use the JNI (native) implementation of physics. Which you choose is up to you.
 
-For a detailed description of the separate jar files see <<ROOT:getting-started/jme3_source_structure.adoc#structure-of-jmonkeyengine3-jars,this list>>.
+include::ROOT:partial$source-structure-link.adoc[]
 
 How you initialize each is the same, only the methods used for manipulating objects is different. The first thing you do in every physics game is create a BulletAppState object. It gives you access to the jME3 Bullet integration which handles physical forces and collisions.