fix: add customShapes in Graphics.js and fix unit test error

Author: VANSH3104

src/core/p5.Graphics.js

@@ -23,6 +23,7 @@ import material from '../webgl/material';
 import creatingReading from '../color/creating_reading';
 import trigonometry from '../math/trigonometry';
 import { renderers } from './rendering';
+import customShapes from '../shape/custom_shapes';
 
 class Graphics {
   constructor(w, h, renderer, pInst, canvas) {
@@ -671,15 +672,13 @@ function graphics(p5, fn){
    * </div>
    */
   p5.Graphics = Graphics;
-  p5.Graphics.prototype.splineVertex = function(x, y, z, u, v) {
-    this._renderer.splineVertex(x, y, z, u, v);
-    return this;
-  };
+  
   // Shapes
   primitives2D(p5, p5.Graphics.prototype);
   attributes(p5, p5.Graphics.prototype);
   curves(p5, p5.Graphics.prototype);
   vertex(p5, p5.Graphics.prototype);
+  customShapes(p5, p5.Graphics.prototype);
 
   setting(p5, p5.Graphics.prototype);
   loadingDisplaying(p5, p5.Graphics.prototype);