Remove unnecessary specularmap_pars_fragment include from physical vertex shader

src/renderers/shaders/ShaderLib/meshphysical_vert.glsl

@@ -17,7 +17,6 @@ varying vec3 vViewPosition;
 #include <morphtarget_pars_vertex>
 #include <skinning_pars_vertex>
 #include <shadowmap_pars_vertex>
-#include <specularmap_pars_fragment>
 #include <logdepthbuf_pars_vertex>
 #include <clipping_planes_pars_vertex>