Robert Marshall authored Sep 13, 2022 and Balasankar 'Balu' C committed Sep 13, 2022

- Refactors the consul watcher recipe for easier reading.
- Fixes the example in the gitlab.rb template which shows configuring a
  complete watcher in the watchers section, when it's really used as
  just a list of strings that indicate which watcher is enabled
- Move the default watcher definition for postgresql into the helper
  because it is directly tied to static values the user cannot change
  such as the name of the failover_pgbouncer template
- Accomodate the potential for folks who may have created their own
  watcher, though if they did it was following a very strict set of
  rules as the ERB template path was hardcoded.

Closes #6562

Closes #3792

Closes #6587



Changelog: changed

Signed-off-by: Robert Marshall <rmarshall@gitlab.com>