`TypeError` when trying to validate a `"nullable": false` property

[leNEKO]

Given a schema:

openapi: 3.0.0
info:
  title: test
  version: test
  description: test
  termsOfService: test
paths:
  /api/data:
    post:
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - value
              properties:
                value:
                  nullable: false
                  oneOf:
                    - type: string
                    - type: boolean
      responses:
        '200':
          description: A response
          content:
            application/json:
              schema:
                type: string

Validating a POST /api/data request with a payload like this:

{
  "value": null
}

Give a TypeError error with the message in_array(): Argument #2 ($haystack) must be of type array, null given message from

openapi-psr7-validator/src/Schema/Keywords/Nullable.php

Line 30 in 6772c57

return ! is_string($this->parentSchema->type) && in_array('null', $this->parentSchema->type);

Instead of a InvalidBody exception.