[UX] Improve error message during generation of configuration

[moretea]

If one makes a typo in a config file, the supervisor prints out a Rust Result directly.

Maybe the supervisor should just abort if the generation of configuration files fails; the current behaviour might lead to starting mis-configured services.

How to reproduce

1. Create an empty plan.sh and a config/some_file
2. Fill config/some_file with:

aaa{{ref}aaa

This will generate an error similar to:

php-redis.default(SR): Failed to write service configuration: hab-sup(SC)[src/manager/service/config.rs:161:27]: TemplateError(TemplateError { reason: InvalidSyntax, template_name: Some("phpfpm.conf"), line_no: Some(6), column_no: Some(32) })

[rsertelon]

This is also linked to and could be fixed with #1137

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We value your input and contribution. Please leave a comment if this issue still affects you.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We value your input and contribution. Please leave a comment if this issue still affects you.