Update stryker monorepo (major) (#140)

* Update stryker monorepo

* test(stryker): Update configuration

to match changes in stryker.
Tried jest-runner but couldn't get it working (doesn't find tests in sandbox).
Running jest with some more arguments to speed up execution.

https://stryker-mutator.io/blog/announcing-stryker-4-mutation-switching
https://stryker-mutator.io/docs/stryker/configuration/

* chore(stryker): Use proper key for comment

Co-authored-by: Renovate Bot <bot@renovateapp.com>
Co-authored-by: Christian Bewernitz <coder@karfau.de>