Fix ConnectionPool deprecation

What does this MR do and why?

We're fixing deprecation problem with ConnectionPool when updating Rails from 7.1 to 7.2

As we're seeing in Update next-rails to 7.2.2.1 (!189168 - merged), there are many failures due to this deprecation message.

References

• Rails 7.2 upgrade (&17620 - closed)
• !189168 (merged)

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Checkout the branch
2. Change current rails version to 7.2+
3. Verify there are no more deprecation messages 🎉

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