Forbid not registered instances deregistration

[arbulu89]

Description

Now that SAP instances deregistration will be triggered by external users, i want to enforce some better rules.
The application and database instances cannot be deregistered if they are not registered already.

PD: the new application_instance_not_registered and database_instance_not_registered atoms will be added to the fallback controller in next PRs, when they are really used

How was this tested?

Tested

[CDimonaco]

LGTM for me, just a nitpick we could order the clauses maybe_emit_application_instance_deregistered_event maybe_emit_database_instance_deregistered_event, to match the actual usage in the aggregate (invert the current order)

But it's really up to you, no strong opinions

[arbulu89]

LGTM for me, just a nitpick we could order the clauses maybe_emit_application_instance_deregistered_event maybe_emit_database_instance_deregistered_event, to match the actual usage in the aggregate (invert the current order)

But it's really up to you, no strong opinions

Oh, yes, you are right! Good catch.
This should be a strong opinion indeed hehe
As we should enforce the order with precedence of occurrence

[CDimonaco]

LGTM for me, just a nitpick we could order the clauses maybe_emit_application_instance_deregistered_event maybe_emit_database_instance_deregistered_event, to match the actual usage in the aggregate (invert the current order)
But it's really up to you, no strong opinions

Oh, yes, you are right! Good catch. This should be a strong opinion indeed hehe As we should enforce the order with precedence of occurrence

You're right, I was not strong on that because in the end they are two different functions and the clauses between same functions are already ordered, anyway lgtm, good job!

[rtorrero]

Thanks @arbulu89, looks good to me 👍