Mrc 5976 - use github actions and ghcr

[M-Kusumgar]

This PR does a couple of related things:

• we move our workflows onto github actions, also featuring sharding of the e2e tests
• we build and push our images to ghcr
• e2e can now run in parallel, index.etest.ts was using the same directory for all the tests so i have made it so each test is now fully independent of each other
• fs.rmdirSync is deprecated in node 20 so switched to fs.rmSync as suggested by them
• some tests in stochastic.etest.ts were being consistently flaky so made them reliable, basically there was another error in the .action-required-msg element flashing so first we wait for that to go away and then test
• deleted buildkite related things and also docker scripts because we use the build and push docker github action to push now
• updated registry when we do docker pull in run-version.sh script
• added a codecov.yml file because codecov project failing because coverage has decreased by 0.07% is more pedantic than a mathematician except that codecov doesnt have nearly as many axioms, so we have the threshold to 2% just being acceptable, also our full project coverage is now 95-100% which is acceptable i think
• added a smoke test script
• created a repo to speed up build process, it just has node 20, git and curl installed

all tests/checks finish in less than 2m generally speaking :)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.71%. Comparing base (8bf94b7) to head (5018d12).
Report is 74 commits behind head on mrc-5945.

Additional details and impacted files

@@             Coverage Diff              @@
##           mrc-5945     #232      +/-   ##
============================================
- Coverage     99.78%   99.71%   -0.07%     
============================================
  Files           160      185      +25     
  Lines          4109     4542     +433     
  Branches        936      985      +49     
============================================
+ Hits           4100     4529     +429     
- Misses            8       12       +4     
  Partials          1        1              

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