Pen color range [0..99]

Attempted bugfix for "Pen Colors repeat each 101 numbers rather than each 100 numbers" as reported in the Scratch forum:
https://scratch.mit.edu/discuss/topic/369220/

src/extensions/scratch3_pen/index.js

@@ -191,13 +191,13 @@ class Scratch3PenBlocks {
     }
 
     /**
-     * Wrap a color input into the range (0,100).
+     * Wrap a color input into the range (0,99).
      * @param {number} value - the value to be wrapped.
      * @returns {number} the wrapped value.
      * @private
      */
     _wrapColor (value) {
-        return MathUtil.wrapClamp(value, 0, 100);
+        return MathUtil.wrapClamp(value, 0, 99);
     }
 
     /**