Fix linter issues

Author: SerafimArts

src/Node/Literal/IntLiteralNode.php

@@ -40,6 +40,7 @@ public static function parse(string $value): static
                 return new static(\PHP_INT_MIN, $value, $inverse);
             }
 
+            /** @phpstan-ignore-next-line : An "$inverse" variable contain numeric-string */
             return new static((int) $inverse, $value, $inverse);
         }
 

src/Node/Literal/VariableLiteralNode.php

@@ -46,6 +46,7 @@ public static function parse(string $value): static
 
     public function getValue(): string
     {
+        /** @var non-empty-string */
         return $this->value;
     }
 }

src/Node/Stmt/Shape/ClassConstMaskFieldNode.php

@@ -20,7 +20,7 @@ public function __construct(
         parent::__construct($of, $optional, $attributes);
     }
 
-    public function getKey(): int|string
+    public function getKey(): string
     {
         $result = $this->key->class->toString()
             . '::' . $this->key->constant?->toString();