Merge pull request #6697 from sudhanshuv1/fix-acos-reference

fixed second example in the reference page for `acos()`

src/math/trigonometry.js

@@ -42,7 +42,7 @@ p5.prototype._angleMode = constants.RADIANS;
  *
  * <div>
  * <code>
- * let a = PI;
+ * let a = PI + QUARTER_PI;
  * let c = cos(a);
  * let ac = acos(c);
  * text(`${round(a, 3)}`, 35, 25);