Remove leftovers/ dead code from #980e287b9a

[piotr-cz]

The package.json contains references in build-sw and fix-asset-manifest to scripts that have been removed in 980e287 and workbox-build package that has been used by one of these.

I've removed these from codebase.

I am not sure about removing the clean-cra-sw script as this cleans up service-worker related artifacts that are generated, but not used anymore but still pushed to mobile app (code bases https://github.com/ProteGO-Safe/android/tree/4.2.4/app/src/main/assets/pwa).

I'd pipe it in build script.

[qLb]

We require Digitally Signed Personal Agreement for Contributors collaborating on the project to accept their Pull Requests - it's Public Health so We need Public Trust thus introducing digital two-factor authentication for The Makers - also Apple doesn't go well with GNU so We make them do so manually by following these steps:

1. Remember STOP COVID - ProteGO Safe software is being released on GNU GENERAL PUBLIC LICENSE
2. If You would like to contribute any changes to our project repositories You are the author and the owner of these changes, by the law of GitHub Terms of Use You automatically grant license for these changes .
3. Mitigating any kind of misunderstanding around copyrights as well as lack of trust for unknown entities in public sector we ask that every Pull Request author verify aforementioned license grants for proposed changes through :
   • Downloading personal license disclaimer form which states that the author:
     • confirms GPL license grant for proposed changes
     • permits everyone and anyone who agrees with the license statements to distribute this software freely in any form or format even in public software providers such as Apple's App Store, Google's Play Store, GitHub, etc.
     • commits the author of changes not to execute his personal copyrights to dismiss them or their license for any reason
   • Digitally signing the completed license statement form with compatible digital signature:
     • Trusted digital signature
     • Qualified digital signature
     • Personal digital signature
   • Sending completed and signed license disclaimer form to protego@mc.gov.pl with:
     • Title: Oświadczenie GitHub
     • Note: Ministry of Digitalization will become your administrator of personal data submitted during process (Szczegóły przetwarzania danych przez każdą z jednostek znajdują się w ich politykach przetwarzania danych osobowych.)
4. After sending completed and signed license disclaimer form You will be added to CONTRIBUTORS.md file on the first merged Pull Request.
5. Then since We accept Pull Requests from new contributors only if they've already sent their completed and signed license disclaimer form thus are present on this list CONTRIBUTORS.md we should process Your future requests much, much faster. Thank You.
6. Last and at least we'd like You to know We're very sorry as We also wish there was a simpler way to do all this and promise to look for it in the future.

[piotr-cz]

It will take me some time to set up Trusted digital signature.

Your instructions are very helpful, I think this could be added in /CONTRIBUTORS.md or .github/CONTRIBUTING.md

[piotr-cz]

Note:

• scripts has been clean up in 02fc160
• workbox-build package is still present

[qLb]

Yes this should be mentioned in those two places You pointed out. I think we'll put some info at the top of those files pointing straight to this so it's easier to find. I think this should be enough.