Address Psalm errors

src/UuidInterface.php

@@ -50,6 +50,10 @@ interface UuidInterface extends JsonSerializable, Serializable
      * The result is true if and only if the argument is not null, is a UUID
      * object, has the same variant, and contains the same value, bit for bit,
      * as the UUID.
+     *
+     * @param object|null $other An object to test for equality with this UUID
+     *
+     * @return bool True if the other object is equal to this UUID
      */
     public function equals(?object $other): bool;