[Heroku] [request]: Mandatory Dyno Restart

### Required Terms

- [X] I agree to follow this project's [Code of Conduct](https://github.com/heroku/roadmap/blob/main/CODE_OF_CONDUCT.md)
- [X] I have read and accept the [Salesforce Program Agreement](https://www.salesforce.com/company/program-agreement/)

### What service(s) is this request for?

Dyno

### Tell us about what you're trying to solve. What challenges are you facing?

```markdown
We run a high availability gateway on Heroku
The daily mandatory Dyno restart is causing issues as we lose availability of the service for this duration
1. Allow selecting dyno restart time
2. Allow granular restart (if we have more than 1 dyno allocated - keep at least one running)
3. If autoscaling is enabled - cycle the dynos

Can be limited to private space at first
```