NameError when updating Heroky Ruby add-on

### Environment

SaaS (https://sentry.io/)

### Steps to Reproduce

1. Have a heroku app with the Sentry heroky add-on using raven-ruby
2. Try to update it to the current version by:
3. Removing the current add-on
4. Follow the steps on this page to configure the current version of ruby: https://devcenter.heroku.com/articles/sentry

### Expected Result

User is able to configure the new version

### Actual Result

The user gets following error in the Heroku logs
```
"NameError (uninitialized constant Middleware::SentryCatcher::Raven)"
```

Originally reported in this [internal ticket.](https://sentry.zendesk.com/agent/tickets/110855)

### Product Area

Settings - Integrations

### Link

_No response_

### DSN

_No response_

### Version

_No response_