LibJS/Tests: Enable Array tests that now just work :^)

Author: https://github.com/linusg
Commit: https://github.com/SerenityOS/serenity/commit/70c6090fef9
Pull-request: https://github.com/SerenityOS/serenity/pull/8262
Reviewed-by: https://github.com/IdanHo
Reviewed-by: https://github.com/alimpfard ✅
Reviewed-by: https://github.com/awesomekling ✅
Reviewed-by: https://github.com/davidot
Reviewed-by: https://github.com/mattco98

Userland/Libraries/LibJS/Tests/builtins/Array/Array.prototype.concat.js

@@ -41,7 +41,7 @@ describe("normal behavior", () => {
         expect(concatenated[5]).toEqual([2, 3]);
     });
 
-    test.skip("Proxy is concatenated as array", () => {
+    test("Proxy is concatenated as array", () => {
         var proxy = new Proxy([9, 8], {});
         var concatenated = array.concat(proxy);
         expect(array).toHaveLength(1);

Userland/Libraries/LibJS/Tests/builtins/Array/array-length-setter.js

@@ -60,7 +60,7 @@ describe("behavior when obj has Array prototype", () => {
     function ArrExtend() {}
     ArrExtend.prototype = [10, 11, 12];
 
-    test.skip("Has the properties from prototype", () => {
+    test("Has the properties from prototype", () => {
         var arr = new ArrExtend();
         expect(arr.length).toEqual(3);
         expect(arr[0]).toEqual(10);
@@ -81,7 +81,7 @@ describe("behavior when obj has Array prototype", () => {
         });
     });
 
-    test.skip("Can call array methods", () => {
+    test("Can call array methods", () => {
         var arr = new ArrExtend();
         arr.push(1);
         expect(arr.length).toEqual(4);