Update docs

docs/20_Checks/check_ceph_diskfree.md

-# check Ceph diskfree
+# Check Ceph diskfree
 
 ## Introduction
 
@@ -61,4 +61,4 @@ OK         .mgr   1    1   18 MiB        6   18 MiB      0     16 TiB
 OK         one    2   32  255 GiB   66.65k  255 GiB   0.50     16 TiB
 OK         two    3   32      0 B        0      0 B      0     25 TiB
  |global-total=59373627899904;;;0;59373627899904 global-avail=58274116272128;;;0;59373627899904 global-used=823559979008;;;0;59373627899904 
-...
+```