Build a Ruby App with CockroachDB and ActiveRecord Doc Update

Artem Ervits (dbist) commented:

Re: [Build a Ruby App with CockroachDB and ActiveRecord](https://cockroachlabs.com/docs/v21.1/build-a-ruby-app-with-cockroachdb-activerecord.html)

## Issue Description

We have logic in our Python, Java and Go Hello World apps to demonstrate how to handle retries. We'd like the same for our active record tutorial, especially that it handles some of the retry logic in the adapter.

## Suggested Resolution

Jira Issue: DOC-1508