Move RPC checks to buildjet

[LesnyRumcajs]

Summary

Lotus occasionally goes OOM (#6026). We can't change Lotus's memory requirements, so if we intend to continue testing on calibnet, we must upgrade the runners.

It should be trivial to switch from GH runner to buildjet with more memory. It's not, see #5905. Regardless, this must be tackled one way or another.

If buildjet doesn't work at all for some reason, we can consider switching to a different alternative runner. There are quite a bit of them out there.

Completion Criteria

• Upgrade runner for RPC compare tests so that Lotus doesn't OOM

Additional Links & Resources

[hanabi1224]

How about a self-hosted runner on Fuzzy?

[LesnyRumcajs]

I don't think it makes sense. The cost of setting it up and maintaining it is non-negligble (plus it turned out to be faulty with data races out of the box). I'd say it's a better use of our time to use an out of the box solution, especially that these workflows are not run very often, so the cost should be fairly low.