Rework tests structure. Upgrade codeception to 2.5.3. Merge params configuration into app configuration.

api/tests/_pages/InternalRoute.php

@@ -0,0 +1,10 @@
+<?php
+namespace api\tests\_pages;
+
+class InternalRoute extends BasePage {
+
+    public function info(string $param, string $value) {
+        $this->getActor()->sendGET('/api/internal/accounts/info', [$param => $value]);
+    }
+
+}