ReleaseNotes inside Deployment are nullable

[marchenko1985]

According to a interfaces it seems that ReleaseNotes should be non nullable string, but in reality it may be null

import { Client, DeploymentRepository } from '@octopusdeploy/api-client'

describe('repro', () => {
  it('has null release notes', async () => {
    const client = await Client.create({
      instanceURL: 'https://sample.octopus.app',
      apiKey: process.env.OCTOPUS_APIKEY,
      userAgentApp: 'sample',
    })
    const deployments = new DeploymentRepository(client, 'Sample')
    const deployment = await deployments.get('Deployments-1')
    expect(deployment.Changes).toHaveLength(1)
    expect(deployment.Changes[0].ReleaseNotes).toBe(null) // <- interfaces vs reality
  })
})