qa: add parallelized cleanup step in _rebuild_metadata()

doc [0] suggests running cleanup step after scanning extents and inodes which was missing in the func `_rebuild_metadata()`
[0] https://docs.ceph.com/en/latest/cephfs/disaster-recovery-experts/#recovery-from-missing-metadata-objects

Signed-off-by: Dhairya Parmar <[email protected]>

Author: dparmar18

qa/tasks/cephfs/test_data_scan.py

@@ -509,6 +509,7 @@ def _rebuild_metadata(self, workload, workers=1, unmount=True):
         self.fs.data_scan(["scan_extents"], worker_count=workers)
         self.fs.data_scan(["scan_inodes"], worker_count=workers)
         self.fs.data_scan(["scan_links"])
+        self.fs.data_scan(["cleanup"], worker_count=workers)
 
         workload.mangle()