Merge pull request #10861 from skyace65/PhysicsInterpolationLink

Update CPU optimization physics interpolation info

Author: mhilbrunner

tutorials/performance/cpu_optimization.rst

@@ -270,8 +270,8 @@ that feature real-time player movement.
 
 The solution to jitter is to use *fixed timestep interpolation*, which involves
 smoothing the rendered positions and rotations over multiple frames to match the
-physics. You can either implement this yourself or use a
-`third-party addon <https://github.com/lawnjelly/smoothing-addon>`__.
+physics. Godot has built-in physics interpolation which you can read about
+:ref:`here<doc_physics_interpolation>`.
 Performance-wise, interpolation is a very cheap operation compared to running a
 physics tick. It's orders of magnitude faster, so this can be a significant
 performance win while also reducing jitter.