Rewrite import feature (#21054)

app/workers/scheduler/vacuum_scheduler.rb

@@ -23,6 +23,7 @@ class Scheduler::VacuumScheduler
       backups_vacuum,
       access_tokens_vacuum,
       feeds_vacuum,
+      imports_vacuum,
     ]
   end
 
@@ -50,6 +51,10 @@ class Scheduler::VacuumScheduler
     Vacuum::FeedsVacuum.new
   end
 
+  def imports_vacuum
+    Vacuum::ImportsVacuum.new
+  end
+
   def content_retention_policy
     ContentRetentionPolicy.current
   end