Fix for Solid Reactive mode bug (#5846)

derp, forgot to remove the pragma once

quantum/rgb_matrix_animations/solid_reactive_simple_anim.h

@@ -1,4 +1,3 @@
-#pragma once
 #ifdef RGB_MATRIX_KEYREACTIVE_ENABLED
 #ifndef DISABLE_RGB_MATRIX_SOLID_REACTIVE_SIMPLE
 RGB_MATRIX_EFFECT(SOLID_REACTIVE_SIMPLE)