LibJS: Use Number instead of parseInt in TypedArray forEach BigInt tests

The Number constructor previously didn't support converting BigInts to
regular numbers, so I used parseInt as a workaround.

Since it now supports this, this workaround is no longer needed.

Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.forEach.js

@@ -95,7 +95,7 @@ describe("normal behaviour", () => {
             const typedArray = new T([1n, 2n, 3n]);
             typedArray.forEach((value, index) => {
                 expect(value).toBe(typedArray[index]);
-                expect(index).toBe(parseInt(typedArray[index] - 1n));
+                expect(index).toBe(Number(typedArray[index] - 1n));
             });
         });
     });