StatefulSet terminationGracePeriodSeconds is too long and not configurable

[panophobicPanda]

Describe the bug
When deleting a pod from the statefulset as defined in thanos/templates/rule-statefulset.yaml , it takes 900 seconds.

Steps to reproduce the issue:

time kubectl delete pod thanos-shard-logan-receive-0
pod "thanos-shard-logan-receive-0" deleted

real	15m7.924s

Expected behavior
The pod should terminate in a reasonable time period (10 seconds is common but anything less then 60 seconds is reasonable).

Additional context
Reducing the value of terminationGracePeriodSeconds in the template is one solution. Or exposing the value to be configurable in thanos/values.yaml is also an option.