pcbnew: don't move twice

In pcbnew, if you press M to move your selection and press M again, then escape, you will trigger the https://gitlab.com/kicad/code/kicad/-/blob/master/common/tool/tools_holder.cpp#L106 assert

pcbnew/tools/edit_tool_move_fct.cpp

@@ -225,7 +225,7 @@ int EDIT_TOOL::PackAndMoveFootprints( const TOOL_EVENT& aEvent )
 
 int EDIT_TOOL::Move( const TOOL_EVENT& aEvent )
 {
-    if( isRouterActive() )
+    if( isRouterActive() || m_dragging )
     {
         wxBell();
         return 0;