fix: workaround for phpstan bug

Author: calebdw

rules/TypeDeclaration/NodeAnalyzer/StrictTypeSafetyChecker.php

@@ -197,6 +197,11 @@ private function isPropertyAssignSafe(Assign $assign): bool
 
     private function isTypeSafeForStrictMode(Type $declaredType, Type $valueType): bool
     {
+        // this is a workaround for a phpstan bug
+        if ($valueType instanceof MixedType) {
+            return $declaredType instanceof MixedType;
+        }
+
         return $declaredType->accepts($valueType, strictTypes: true)
             ->yes();
     }