fixup: linting and add comment

Signed-off-by: Kairo de Araujo <[email protected]>

repository_service_tuf_worker/repository.py

@@ -736,7 +736,7 @@ def _remove_delegated_role_keys(
             if key not in other_keys:
                 logging.debug(f"removing key id {key}")
                 targets.signed.delegations.keys.delete(key)
-             else:
+            else:
                 logging.debug(f"key {key} used by other role")
 
     def _add_delegated_role_keys(
@@ -1034,6 +1034,9 @@ def _bootstrap_online_roles(
             logging.debug("verifying delegations threshold")
             for role in success:
                 if self._validate_threshold(success[role], targets, role):
+                    # If the role uses online key it was signed by while
+                    # adding the role by self._add_metadata_delegation.
+                    # if the threshold is met, role is full signed
                     logging.debug(f"role '{role}' uses only online key")
                     snapshot.signed.meta[f"{role}.json"] = MetaFile(
                         success[role].signed.version