Tests: remove prepDb workaround

Previously, the `prepareDatabase` method would directly modify the database, booting the app in the process. This would prevent any extenders from being applied, since `->extend()` has no effect once the app is booted.

Since the new implementation of `prepareDatabase` simply registers seed data to be applied during app boot, the workaround of sticking this seed data into `prepDb` is no longer necessary, and seed data common to all test cases in a class can be provided in `setUp`.

When needed, app boot is explicitly triggered in individual test cases by calling `$this->app()`.

tests/integration/extenders/ApiSerializerTest.php

@@ -27,8 +27,13 @@ class ApiSerializerTest extends TestCase
 {
     use RetrievesAuthorizedUsers;
 
-    protected function prepDb()
+    /**
+     * @inheritDoc
+     */
+    protected function setUp(): void
     {
+        parent::setUp();
+
         $this->prepareDatabase([
             'users' => [
                 $this->normalUser()
@@ -42,8 +47,6 @@ class ApiSerializerTest extends TestCase
                 ['id' => 1, 'discussion_id' => 3, 'created_at' => Carbon::now()->toDateTimeString(), 'user_id' => 2, 'type' => 'discussionRenamed', 'content' => '<t><p>can i haz relationz?</p></t>'],
             ],
         ]);
-
-        $this->app();
     }
 
     /**
@@ -329,8 +332,6 @@ class ApiSerializerTest extends TestCase
                 ->hasMany('customSerializerRelation', DiscussionSerializer::class)
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);
@@ -356,8 +357,6 @@ class ApiSerializerTest extends TestCase
                 ->hasOne('customSerializerRelation', DiscussionSerializer::class)
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);
@@ -385,8 +384,6 @@ class ApiSerializerTest extends TestCase
                 })
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);
@@ -412,8 +409,6 @@ class ApiSerializerTest extends TestCase
                 ->relationship('customSerializerRelation', CustomRelationshipInvokableClass::class)
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);
@@ -439,8 +434,6 @@ class ApiSerializerTest extends TestCase
                 ->hasMany('anotherCustomRelation', DiscussionSerializer::class)
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);
@@ -472,8 +465,6 @@ class ApiSerializerTest extends TestCase
                 })
         );
 
-        $this->prepDb();
-
         $request = $this->request('GET', '/api/users/2', [
             'authenticatedAs' => 1,
         ]);