[BUG] [typescript-angular] Array with nullable values generated as array with non-nullable values

Description

Trying to get array with nullable values, for example Array<Book | null>, I get Array<Book>

openapi-generator version

6.2.1

OpenAPI declaration file content

components:
    schemas:
        Library:
            type: object
            required: [books]
            properties:
                books:
                    type: array
                    items:
                        nullable: true
                        $ref: "#/components/schemas/Book"
        Book:
            type: object
            nullable: true
            properties:
                title:
                    type: string

Start with the typescript-angular generator and the supplied OpenAPI declaration, then inspect the generated type for Library.books. Compare the output with the expected Array<Book | null>; done means nullable array items are preserved in the generated TypeScript model.