CNG: Specify STOPSIGNAL for processes that don't listen to SIGTERM

Summary

In #3249 (comment 935872036) we've looked at all our usage of pkill and found out some of them only exist because the process listens to a different signal instead of SIGTERM (default signal send on container termination).

A Dockerfile can have STOPSIGNAL which specifies what signal to send instead of SIGTERM. This would make graceful termination the default behavior outside of the helmchart.

Containers to update

• webservice
  • Add STOPSIGNAL
  • Remove pkill
• geo-logcuros
  • Add STOPSIGNAL
  • Remove pkill