Post provisioning ssh check configuration

The feature which made post provisioning ssh check configurable is using the post_provisioning_check section from provisioning-config.yaml. An example is shown down below with the inline comments:

post_provisioning_check:
    ssh:
        # Default configurations for every host
        enabled: True # True | False
        disabled_providers: ["podman"] # Per provider override to `enabled: True`
        enabled_providers: [] # Would be relevant if 'enabled' is 'False'
        # port: 22
        # timeout: 10 # minutes

        # Overrides
        # Priority:
        # OS > Group > Default

        group:
            ipaclient:
                timeout: 309090 # minutes
        # If we want to override based on OS
        os:
            win-2012r2:
                timeout: 15 # minutes
            win-2016:
                timeout: 15 # minutes
            win-2019:
                timeout: 15 # minutes
            fedora-34:
                enabled: False
                timeout: 1
                enabled_providers: ["static"]
                disabled_providers: ["beaker"]

Priority is set to: OS > Group > Default which implies that per group configuration overrides the default config and os overrides both default and group.

When the post_provisioning_check section is not set mrack uses these defaults:

enabled: True
enabled_providers: []
disabled_providers: []
port: 22
timeout: 10