tasks: improve behaviour on upgrade

when upgrading from a version where we stored all tasks in the 'active' file,
we did not completly account for finished tasks still there

we should update the file when encountering any finished task in
'active' as well as filter them out on the api call (if they get through)

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

src/api2/node/tasks.rs

@@ -352,6 +352,7 @@ pub fn list_tasks(
         }
 
         match info.state {
+            Some(_) if running => return None,
             Some(crate::server::TaskState::OK { .. }) if errors => return None,
             _ => {},
         }

src/server/worker_task.rs

@@ -539,7 +539,7 @@ impl TaskListInfoIterator {
 
             let needs_update = active_list
                 .iter()
-                .any(|info| info.state.is_none() && !worker_is_active_local(&info.upid));
+                .any(|info| info.state.is_some() || !worker_is_active_local(&info.upid));
 
             if needs_update {
                 drop(lock);