Adds relationship to PostFactory fixture

Author: axit-joost

tests/fixtures/factories/post.php

@@ -8,7 +8,7 @@
 $factory->define(Post::class, function (Faker $faker) {
     return [
         'title' => $faker->sentence(4),
-        'author_id' => $faker->randomDigitNotNull,
+        'author_id' => factory(\App\Author::class),
         'content' => $faker->paragraphs(3, true),
         'published_at' => $faker->dateTime(),
         'word_count' => $faker->randomNumber(),