Update Validators to extend ABC instead of implementing interface.

app/Models/Validation/Validators/Validator.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Models\Validation\Validators;
+
+abstract class Validator {
+    abstract public function isCurrentValid(): bool;
+
+    public function isValid(): bool
+    {
+        return $this->isCurrentValid() && $this->nextValidator->isValid();
+    }
+}
+