Merge pull request #21748 from b-ranto/wip-fix-prom-shutdown

prometheus: Fix prometheus shutdown/restart

Reveiwed-by: John Spray <john.spray@redhat.com>
Reviewed-by: Jan Fajerski <jfajerski@suse.com>

diff --cc src/pybind/mgr/prometheus/module.py
index f7347f8408ae0644bfcd40d1cc3533975bcda6eb,858adf6e143303c82291e673a7956a0e1bece232..aac656e407ee5693a4512e0088948092248903b9
--- 1/src/pybind/mgr/prometheus/module.py
--- 2/src/pybind/mgr/prometheus/module.py
+++ b/src/pybind/mgr/prometheus/module.py
@@@ -4,8 -4,9 +4,9 @@@ import errn
  import math
  import os
  import socket
+ import threading
  from collections import OrderedDict
 -from mgr_module import MgrModule, MgrStandbyModule
 +from mgr_module import MgrModule, MgrStandbyModule, CommandResult
  
  # Defaults for the Prometheus HTTP server.  Can also set in config-key
  # see https://github.com/prometheus/prometheus/wiki/Default-port-allocations