A test model that uses a custom suffix generation method.
Inheritance: extends Cviebrock\EloquentSluggable\Tests\Models\Post
 /**
  * Test using a custom separator.
  *
  * @test
  */
 public function testCustomSeparator()
 {
     $post = PostWithCustomSeparator::create(['title' => 'A post title']);
     $this->assertEquals('a.post.title', $post->slug);
 }