[Feature] Modify/disable Healthcheck time interval

[maximeMD]

Context

I'm using Neon for serverless postgres, and I don't want pgbackweb to wake up my db every 10mn, I chose Neon specifically to scale to zero.
My need is to disable healthchecks, or maybe set it to "every hour" for example.

Another use case would be to reduce the time interval (for like 1mn) for sensible production environments monitoring.

Suggested Stories

From (what seems) the easiest to the hardest to implement :

• As a sysadmin,
  I want to be able to set an environment variable (like HEALTHCHECK_ACTIVE)
  in order to enable/disable healthchecks

• As a sysadmin,
  I want to be able to set an environment variable (like HEALTHCHECK_INTERVAL)
  in order to set the healthcheck time interval.

• As a user
  I want to have access to a switch in the global options
  In order to enable/disable healthchecks

• As a user
  I want to have access to an input in the global options
  In order to set the healthcheck time interval

• As a user
  I want to have access to a switch option for each database
  In order to enable/disable healthchecks for a specific database

• As a user
  I want to have access to an input option for each database
  In order to set the healthcheck time interval for a specific database