CHANGED - pin actions, use updated self-hosted runners

[waskow-consensys]

When using Third Party Actions, pinning allows for not only consistent CI Runs, as no underlying changes with the action are promoted unknowingly.
https://docs.github.com/en/actions/security-for-github-actions/security-guides/security-hardening-for-github-actions#using-third-party-actions

Additionally, use new config for updated self-hosted runners.

[cla-assistant]

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[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.18%. Comparing base (1ad6131) to head (9b7aefc).

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #550   +/-   ##
=========================================
  Coverage     68.18%   68.18%           
  Complexity     1129     1129           
=========================================
  Files           320      320           
  Lines         12855    12855           
  Branches       1292     1292           
=========================================
  Hits           8765     8765           
  Misses         3558     3558           
  Partials        532      532           

Flag	Coverage Δ		*Carryforward flag
hardhat	98.74% <ø> (ø)		Carriedforward from 1ad6131
kotlin	65.71% <ø> (ø)

*This pull request uses carry forward flags. Click here to find out more.

[waskow-consensys]

FYI @kyzooghost