doc/cephadm: s/confg/config/

Correct a misspelled command.

Re: ceph#62367 (comment)

Signed-off-by: Zac Dover <[email protected]>

Author: zdover23

doc/cephadm/upgrade.rst

@@ -59,7 +59,7 @@ Starting the upgrade
 
    .. prompt:: bash #
 
-      ceph confg set mgr mgr/orchestrator/fail_fs true
+      ceph config set mgr mgr/orchestrator/fail_fs true
 
    This would:
                #. Fail CephFS filesystems, bringing active MDS daemon(s) to