Extend wbi to include HA configurations

[samcofer]

In phase 2, we should enable wbi to configuration HA configurations and include commentary to tell folks what they need to do once we're done with the installer. The core areas that need to be checked/built are here:

1. /etc/rstudio/load-balancer needs to be created and populated
2. Prompts to input Postgres DB connection information, and validate connectivity to database
3. Prompt for NFS storage configuration, test NFS storage for project sharing/acl support

HA page link: https://docs.posit.co/rsw/configuration/high-availability-launcher/