docs: fix references to old 'cleaner' service #7920
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Motivation:
The docs contains some obsolete references to the
cleanercell.Motification:
Update these to
cleaner-disk, the new name for this cell.Result:
Document updated to reflect rename of 'cleaner' to 'cleaner-disk'.
Target: master
Request: 10.2
Request: 10.1
Request: 10.0
Request: 9.2
Patch: https://rb.dcache.org/r/14397/
Acked-by: Tigran Mkrtchyan