Add 'Endorsing, sponsoring and supporting visa applicants'
user
```ruby
MainstreamCategory.create!(
  slug: "endorsing-sponsoring-and-supporting-visa-applicants",
  title: "Endorsing, sponsoring and supporting visa applicants",
  parent_title: "Employers' sponsorship",
  parent_tag: "visas-immigration/employers-sponsorship",
  description: "Information for employers, educators and legal practitioners on endorsing and sponsoring visa applicants, and getting refugees the support they're entitled to."
)
```
assistant