test user login and create fake user repo

tests/Fakes/User/FakeUserRepository.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Tests\Fakes\User;
+
+use FreightQuote\User\User;
+use FreightQuote\User\UserRepository;
+
+class FakeUserRepository implements UserRepository
+{
+    /**
+     * @var User[] $existingUsers
+     */
+    private array $existingUsers = [];
+
+    public function findByEmail(string $email): ?User
+    {
+        foreach ($this->existingUsers as $user) {
+            if ($user->getEmail() === $email) {
+                return new User(
+                    $user->getEmail(),
+                    $user->getPassword()
+                );
+            }
+        }
+
+        return null;
+    }
+
+    public function save(User $user): User
+    {
+        $this->existingUsers[$user->getEmail()] = $user;
+
+        return new User($user->getEmail(), $user->getPassword());
+    }
+}