Clarify issue/PR choreography

From a discussion with @picnixz:

I think the problem with the devguide is the first sentence is "Create an issue that describes the change" and you'll see the mention to DPO only during creation. We can improve that
I would expect people to read the issue template correctly and understand that something is not trivial
and more importantly: WAIT for triagers to decide whether it's ok or not as an issue
There are obvious cases where the issue doesn't a triager for validation, like a clear bug (and even this is subject to interpretation sometimes) but the process issue+PR is the worst for triagers, especially when the PR is automated.

This might be a duplicate of other feedback here in issues, but I wanted to capture it before going back to $WORK.

Comienza localizando las instrucciones iniciales del devguide y la plantilla de issue; después, revisa dónde se introducen las indicaciones sobre DPO y los triagers. Aclara que los contributors deben esperar a la validación de un triager antes de abrir un PR, señalando al mismo tiempo la discusión sobre los bugs claros. Se considera terminado cuando el flujo de trabajo de issue-to-PR y las excepciones están explícitos para los contributors.