Fix DeprecationProviderTest for PHP < 8.0

Author: ondrejmirtes

tests/PHPStan/Reflection/Deprecation/data/CustomDeprecationExtension.php

@@ -33,7 +33,10 @@ class CustomDeprecationExtension implements
 EnumCaseDeprecationExtension
 {
 
-public function getClassDeprecation(ReflectionClass|ReflectionEnum $reflection): ?Deprecation
+/**
+ * @param ReflectionClass|ReflectionEnum $reflection
+ */
+public function getClassDeprecation($reflection): ?Deprecation
 {
 return $this->buildDeprecation($reflection);
 }