investigate YML ruleset parsing

[jeffhostetler]

We were expecting that a undefined section in the YML would cause an error, rather than silently being ignored. Is there an option for this in the YML parser and/or do we need to validate the resulting dictionary for unknown/unexpected keys?

https://github.com/git-ecosystem/trace2receiver/issues/24#issuecomment-2027717356

This is not urgent, but it would be nice to avoid such confusion in the future.