Improve process object creation

[mjesun]

This PR improves the way the process object is created in two ways:

1. It aims to rewrite the way deep cyclic cloning is done:
   1. It uses a specialized method for Arrays.
   2. It copies properties by using getOwnPropertyDescriptors and defineProperties.
   3. It gives a blacklist argument for the root level object.
      ​
2. Using the blacklist, it avoids copying mainModule, which contains a reference to the main module, plus all of the other modules loaded so far in memory.

The total improvement on a raw Node instance is approximately of 40%; but the improvement grows as the amount of previously loaded modules also grows. In my case, I've been able to observe up to 20x performance by artificially loading a bunch of modules before calling createProcessObject.

[mjesun]

Infinite amount of thanks to @thymikee who identified the offending commit by performing a manual bisection!

[codecov-io]

Codecov Report

Merging #4955 into master will decrease coverage by 0.05%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #4955      +/-   ##
==========================================
- Coverage   60.34%   60.29%   -0.06%     
==========================================
  Files         198      198              
  Lines        6604     6598       -6     
  Branches        4        3       -1     
==========================================
- Hits         3985     3978       -7     
- Misses       2619     2620       +1

Impacted Files	Coverage Δ
packages/jest-util/src/create_process_object.js	100% <100%> (ø)	⬆️
packages/jest-util/src/deep_cyclic_copy.js	100% <100%> (ø)	⬆️
packages/jest-runtime/src/script_transformer.js	85.35% <0%> (-1.16%)	⬇️
packages/jest-util/src/install_common_globals.js	100% <0%> (ø)	⬆️

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[thymikee]

Can confirm it's back to the nominal speed on my testing suite 👍

[cpojer]

Thanks for fixing this issue. I would prefer having a whitelist rather than a blacklist. If the node folks decide to add process.allModules = require.cache we have to be pro-active and fix it, otherwise people on old versions of Jest and new versions of node get a dramatic slowdown :(

[github-actions]

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