simulation: Stop on SIGTERM

[ValarDragon]

• Targeted PR against correct branch (see CONTRIBUTING.md)

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work. - Randomized Simulation wishlist #1924

• Wrote tests - n/a?

• Added entries in PENDING.md with issue #

• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[ValarDragon]

Lint failure is unrelated, but also is fixed in #2273.

[codecov]

Codecov Report

Merging #2274 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #2274   +/-   ##
========================================
  Coverage    63.73%   63.73%           
========================================
  Files          140      140           
  Lines         8642     8642           
========================================
  Hits          5508     5508           
  Misses        2755     2755           
  Partials       379      379

Addressed.

[cwgoes]

Tested ACK