Ignore PHPStan's ClassReflection::isEnum error when analyzing the extension code on PHP 7.4

The error is unintentional and maybe it will be resolved soon, but until then let's ignore it.

See phpstan/phpstan#12888

Author: spaze

phpstan-ignore-errors.php

@@ -0,0 +1,18 @@
+<?php
+declare(strict_types = 1);
+
+$config = [
+	'parameters' => [
+		'ignoreErrors' => [],
+	]
+];
+
+if (PHP_VERSION_ID < 80000) {
+	// https://github.com/phpstan/phpstan/discussions/12888
+	$config['parameters']['ignoreErrors'][] = [
+		'message' => '#^Call to method PHPStan\\\\Reflection\\\\ClassReflection::isEnum\\(\\) will always evaluate to false\\.$#',
+		'reportUnmatched' => false,
+	];
+}
+
+return $config;

phpstan.neon

@@ -17,6 +17,7 @@ parameters:
 			- src/PHPStan1Compatibility.php
 
 includes:
+	- phpstan-ignore-errors.php
 	- vendor/phpstan/phpstan/conf/bleedingEdge.neon
 	- vendor/phpstan/phpstan-deprecation-rules/rules.neon
 	- extension.neon