LibJS: Convert most builtin tests to new system

Author: https://github.com/mattco98
Commit: 3f97d75778
Pull-request: https://github.com/SerenityOS/serenity/pull/2689
Reviewed-by: https://github.com/linusg

Libraries/LibJS/Tests/builtins/Math/Math.sqrt.js

@@ -1,7 +1,4 @@
-load("test-common.js");
-
-try {
-    assert(Math.sqrt(9) === 3);
-    console.log("PASS");
-} catch {
-}
+test("basic functionality", () => {
+    expect(Math.sqrt).toHaveLength(1);
+    expect(Math.sqrt(9)).toBe(3);
+});