feat(drush migrate:rollback): skip disabled migrations

src/Drush/Commands/MigrateToolsCommands.php

@@ -577,6 +577,10 @@ class MigrateToolsCommands extends DrushCommands {
       // Roll back in reverse order.
       $migration_list = array_reverse($migration_list);
       foreach ($migration_list as $migration_id => $migration) {
+        // Skip disabled migrations.
+        if ($migration->getStatus() == MigrationInterface::STATUS_DISABLED) {
+          continue;
+        }
         if ($options['skip-progress-bar']) {
           $migration->set('skipProgressBar', TRUE);
         }