LibJS: Indent tests with 4 spaces instead of 2

Author: https://github.com/mattco98
Commit: 1ef573eb30
Pull-request: https://github.com/SerenityOS/serenity/pull/2689
Reviewed-by: https://github.com/linusg

Libraries/LibJS/Tests/functions/constructor-basic.js

@@ -1,11 +1,11 @@
 test("basic functionality", () => {
-  function Foo() {
-    this.x = 123;
-  }
+    function Foo() {
+        this.x = 123;
+    }
 
-  expect(Foo.prototype.constructor).toBe(Foo);
+    expect(Foo.prototype.constructor).toBe(Foo);
 
-  const foo = new Foo();
-  expect(foo.constructor).toBe(Foo);
-  expect(foo.x).toBe(123);
+    const foo = new Foo();
+    expect(foo.constructor).toBe(Foo);
+    expect(foo.x).toBe(123);
 });