test: optimize test runner for e2e-tests and ci

[TarikGul]

1. This optimizes the test runner for the e2e tests by assigning the max concurrent workers, and the allotted CPU that is available. It also uses a trick to isolateModules since our test runner utilizes ts-jest (And by nature is slow).

2. Use --runInBand for running CI tests to not abuse CPU usage in the github actions runner.

[Imod7]

LGTM!
Just some additional ideas in case it is interesting for you (from this write up) :

• jest-offline ?
• upgrade to jest 28 ?
• use jest-slow-test-reporter to identify the slowest tests ?
• switch to @swc/jest ?

Actually all 7 suggestions are interesting to check if you have time (MaxWorkers=50% is one of them :) )

[TarikGul]

LGTM! Just some additional ideas in case it is interesting for you (from this write up) :

• jest-offline ?
• upgrade to jest 28 ?
• use jest-slow-test-reporter to identify the slowest tests ?
• switch to @swc/jest ?

Actually all 7 suggestions are interesting to check if you have time (MaxWorkers=50% is one of them :) )

Oooo Thanks for the link to the write up. So I do know updating to jest 28 causes some issue in substrate-js-dev to sidecar. Maybe we can explore into solving that issue, it has to do with all the plugins that we use. jest-offline sounds interesting as well. I'll have a look at it, and see what we can add

[TarikGul]

So Im going to merge this in, lets focus on the next set of optimizations by updating jest in substrate-js-dev. I'll make an issue there about it so we can move it into here when its done.