Update MutatingScope.php

Author: staabm

src/Analyser/MutatingScope.php

@@ -3233,7 +3233,8 @@ public function filterBySpecifiedTypes(SpecifiedTypes $specifiedTypes): self
 							$conditionalExpression->getTypeHolder()->getCertainty()->yes()
 							&& $specifiedHolder->getCertainty()->yes()
 							&& $conditionalTypeHolder->getCertainty()->yes()
-							&& $guardType->isArray()->no()
+							&& $guardType->isOffsetAccessible()->no()
+							&& TypeUtils::getAccessoryTypes($guardType) === []
 							&& $guardType->isSuperTypeOf($specifiedType)->yes()
 						) {
 							$subtypeMatch = true;