Add Rector & various upgrades

tests/Feature/ReleaseNotesReachabilityTest.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace Feature;
+
+use Tests\TestCase;
+
+class ReleaseNotesReachabilityTest extends TestCase
+{
+    public function test_release_notes_is_reachable()
+    {
+        $response = $this->get('/early-access/release-notes');
+
+        $response->assertStatus(200);
+    }
+}