chore(*): Add 'jest coverage' script to all the packages

[saul-atomrigs]

Overview

This PR adds "coverage": "jest --coverage" script to all the packages' package.json:

.
With this change, now the developer may run the test coverage inspection from VSCode's NPM scripts by clicking on the following:

and get the test coverage result table in the terminal like so:

PR Checklist

• [✅] I read and included theses actions below

1. I have read the Contributing Guide
2. I have written documents and tests, if needed.

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[raon0211]

Thanks!

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