Use Codeception\TestInterface::getName() instead of Codeception\TestInterface::getMetadata()

This commit changes the code to use $event->getTest()->getName() instead
of $event->getTest()->getMetadata()->getName() to get the name of the
current test. This was necessary because the latter was returning null
for integration tests while the former works both for acceptance and
integration tests. I did not investigate why Codeception behaves this
way due to lack of time, there is a chance that this is a bug in
Codeception.

Since $event->getTest() returns an instance of TestInterface and this
class does not define getName() (but the call works probably due to some
magic method), it was necessary to edit phpstan.neon to skip a PHPStan
error.

[MAILPOET-4765]

mailpoet/tasks/phpstan/phpstan.neon

@@ -74,6 +74,10 @@ parameters:
       message: '/^Cannot call method get\(\) on mixed.$/'
       count: 1
       path: ../../lib/PostEditorBlocks/WooCommerceBlocksIntegration.php
+    -
+      message: '/^Call to an undefined method Codeception\\TestInterface::getName()./'
+      count: 1
+      path: ../../tests/_support/CheckSkippedTestsExtension.php
   reportUnmatchedIgnoredErrors: true
   dynamicConstantNames:
     - MAILPOET_PREMIUM_INITIALIZED

mailpoet/tests/_support/CheckSkippedTestsExtension.php

@@ -12,7 +12,7 @@ class CheckSkippedTestsExtension extends Extension {
 
   public function checkSkippedTests(FailEvent $event) {
     $branch = getenv('CIRCLE_BRANCH');
-    $testName = $event->getTest()->getMetadata()->getName();
+    $testName = $event->getTest()->getName();
 
     // list of tests that are allowed to be skipped on trunk and release branches
     $allowedToSkipList = [