LibJS: Fix byteOffset copy-paste error in TypedArray buffer test

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

@@ -20,7 +20,7 @@ test("basic functionality", () => {
         if (!isBigIntArray) typedArray = new T([1, 2, 3]);
         else typedArray = new T([1n, 2n, 3n]);
 
-        expect(Object.hasOwn(typedArray, "byteOffset")).toBeFalse();
+        expect(Object.hasOwn(typedArray, "buffer")).toBeFalse();
 
         const buffer = typedArray.buffer;
         expect(buffer).toBeInstanceOf(ArrayBuffer);