How to use the cwlts/models.DockerRequirementModel function in cwlts

it("should write dockerRequirement.dockerPull to input field", () => {
        component.docker = new DockerRequirementModel({
            class: "DockerRequirement",
            dockerPull: "ubuntu"
        });

        fixture.detectChanges();

        fixture.whenStable().then(() => {
            el = fixture.debugElement.query(By.css("[data-test='docker-pull-input']")).nativeElement;
            expect(el.value).toEqual("ubuntu", "Did not set dockerPull value on input field");
        });
    });

ngOnChanges(): void {
        this.docker = this.docker || new DockerRequirementModel();
    }
}