This commit introduces significant improvements to our backup and recovery capabilities with pgBackRest. The main feature is the ability to configure and manage the dedicated pgBackRest servers. Previously, backup configuration was limited to the database servers only.

The primary advantages of this change are:

Separation of concerns: It enables administrators to maintain dedicated backup servers, which can increase the robustness and reliability of the backup and recovery process.

Flexibility: The backup servers can be configured differently than the database servers, allowing for more tailored backup and recovery scenarios.

Backup cron jobs: In addition to these improvements, this commit introduces the ability to manage pgBackRest cron jobs via the "pgbackrest_cron_jobs" variable. Backup Jobs will be automatically configured.

Additionally:

Docker containers (for Molecule) are configured for ssh interaction. This allows we to test roles for configuring ssh keys.

Updated the pgBackRest configuration template to enable configuration of a single dedicated pgBackRest server for multiple Postgres clusters.

Added support for the include-path option, allowing inclusion of additional configuration files.

Introduced a global section to configure global settings, iterating over the pgbackrest_server_conf.global list for values.

Utilized the include-path directive to include configuration files for stanzas from the specified path ({{ pgbackrest_conf_file | dirname }}/conf.d).

These updates provide the ability to configure a dedicated pgBackRest server for multiple Postgres clusters, enhancing flexibility in managing backup and restore operations across multiple environments.