Fixes typo

Author: Tobias Brandt

config/corneish_zen.keymap

@@ -715,7 +715,7 @@ behaviors {
                 sym_layer {
                         label = "SYM";
 // --------------------------- SYM Layer ---------------------------
-// |  &  |  %  |  #  |  !  |  ?  |  *  |  +  |  @  |  $  |  ^  |
+// |  &  |  %  |  #  |  !  |  \  |  *  |  +  |  @  |  $  |  ^  |
 // |  (  |  [  |  ]  |  )  | DEL | BSPC|  }  |  :  |  -  |  {  |
 // |  '  |  {  |  }  |  "  |  `  |  ?  |  =  |  /  |  .  |  ,  |
 //             |     | SPC |     |     | SPC |     |