Tidy up our CI configurations

[qwwdfsad]

• Migrate to https://www.jetbrains.com/help/teamcity/github-checks-trigger.html from commit-status-publisher to properly handle branch protection rules
• Figure out what is happening with our stress test configuration or remove it completely -- right now, it mostly timeouts because we have a multitude of lincheck tests that take dozens of minutes under a stress test multiplier
• Fixup OS X builds that are diverged from the configuration we are sticking with

[dkhalanskyjb]

• consider separating tests into two groups: smoke tests (that should take less than a minute for the whole build to check them) and acceptance tests; consider launching smoke tests separately, maybe as a GitHub Actions process. Most of our changes never touch anything that needs stress testing, but we still pay the price in development velocity while we wait for the full test suite to complete both locally and on TeamCity.