Fix gt and lt operators

Forgot to capitalize the function name for Push.

starfish.js

@@ -227,13 +227,13 @@ class CodeBox {
                 case "(": {
                     const x = this.stack.Pop();
                     const y = this.stack.Pop();
-                    this.stack.push(y < x ? 1 : 0);
+                    this.stack.Push(y < x ? 1 : 0);
                     break;
                 }
                 case ")": {
                     const x = this.stack.Pop();
                     const y = this.stack.Pop();
-                    this.stack.push(y > x ? 1 : 0);
+                    this.stack.Push(y > x ? 1 : 0);
                     break;
                 }
                 case "=": {