ceph-mixin: Add Prometheus Alert for Degraded Bond

ceph-mixin: Add Prometheus Alert for Degraded Bond

Currently there is no alert for a network interface card to be misconfigured or
failed which is part of a network bond.

This could lead to redundancies and performance being degraded unnoticed.

To solve this, I use node exporter metrics to look at the number of total peers
of the bond and the ones that are active. If the numbers differ, something is up
and should be looked at.

Fixes: https://tracker.ceph.com/issues/57962
Signed-off-by: Christian Kugler <syphdias+git@gmail.com>