Fix code tab (#2290)

Author: Gold856

source/docs/software/advanced-controls/controllers/pidcontroller.rst

@@ -147,6 +147,7 @@ By default, ``IZone`` is disabled.
     pid.setIZone(2);
 
   .. code-tab:: c++
+
     // Disable IZone
     pid.SetIZone(std::numeric_limits<double>::infinity());