[SSSD] [sssd PR#960][opened] server/be: fix incorrect handling of SIGTERM

[alexey-tikhonov]

   URL: https://github.com/SSSD/sssd/pull/960
Author: alexey-tikhonov
 Title: #960: server/be: fix incorrect handling of SIGTERM
Action: opened

PR body:
"""
Fixes https://pagure.io/SSSD/sssd/issue/4088 / cleans up some leftovers after #821
"""

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/960/head:pr960
git checkout pr960