Announce application full DC removal

[jbesraa]

1. Create and endpoint /application/{id}/removed

2. change the state accordingly

pub state: AppState,
pub validated_at: String,
pub validated_by: String,

3. change the allocation requests accordingly
   the new allocation request type should be "removed"

4. a new pr should be opened and immediatly merged with the changes mentioned above

5. the issue related to the application should be also closed

6. add to the E2E test flow (just test it basically)