ui: ceph: allow muting a health check from the health panel

The health panel showed which checks Ceph has muted, but muting itself
was only possible from the command line. The action goes into the
detail of the row that reports the check, where there is room for an
icon and a label.

Muting asks for a duration and for whether the mute should survive the
check getting worse. Both default to no expiry and to clearing the
mute once more items are affected. Unmuting only asks for
confirmation.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>