Currently, the tablet repair scheduler repairs all replicas of a tablet.
It does not support hosts or DCs selection. It should be enough for most
cases. However, users might still want to limit the repair to certain
hosts or DCs in production. #21985 added the preparation work to add the
config options for the selection. This patch adds the hosts or DCs
selection support.
Fixes#22417
(cherry picked from commit 5545289bfa)
6d5b029812