feat: let user specify multiple replica count for pgbouncer

[benoittgt]

What does your PR do?

We want to have more than one replica to be sure we have everything up an running, especially during deployment phase (in our case).

Checklist

For all Pull Requests

• Commits are signed off
• Commits have semantic messages
• Documentation updated
• Passes ct linting

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[y-tee]

hi @thesuperzapper any plans on proceeding with this? this is a very useful feature addition to us as well

[stale]

This issue has been automatically marked as stale because it has not had activity in 60 days.
It will be closed in 7 days if no further activity occurs.

Thank you for your contributions.

---

Issues never become stale if any of the following is true:

1. they are added to a Project
2. they are added to a Milestone
3. they have the lifecycle/frozen label

[benoittgt]

It should be merged. :)

[stale]

This issue has been automatically marked as stale because it has not had activity in 60 days.
It will be closed in 7 days if no further activity occurs.

Thank you for your contributions.

---

Issues never become stale if any of the following is true:

1. they are added to a Project
2. they are added to a Milestone
3. they have the lifecycle/frozen label

[benoittgt]

One last try. 👋