Feature Request: pg_cron configurable OR provide an image without it

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**Describe the Feature Request**
Allow for a way to exclude the pg_cron shared library OR provide a new image without pg_cron.

See support ticket https://support.circleci.com/hc/en-us/requests/145723

**Is your feature request related to a particular problem?**
The current image comes with pg_cron configured out of the box. This means that the pg_cron scheduler is launched on boot which will hold on to a connection to any test database. This is not ideal, since it breaks any build pipeline depending on dropping a test database as part of any test setup code (this is very common in a Rails app, for example).

We are unable to upgrade our build pipeline to anything after PG14.8. I believe there was a fix to pg_cron for 14.9. We are currently trying to upgrade to PG15.5, with the same problem.

**How will this feature request benefit CircleCI jobs using this image?**
We and others will be able to upgrade to an image after PG14.8 if we have jobs relying to dropping a database before setting it up for tests etc.

**Describe the solution you would like to see**
I'd like an easy configuration setting in the config.yml file OR a new image without the pg_cron shared libraries installed.

**Describe alternatives you have considered**
Adding custom logic to the build pipeline that terminates the pg_cron scheduler. This does add a certain amount of tech debt in our build pipeline - but, more importantly, it doesn't actually work since the pg_cron scheduler restarts itself when the pid is terminated.