Don't rebuild during the release process

[jjspace]

Description

The past couple releases we've had some extra .map.js files bleed through into the published version. These cause warnings for users downstream. See https://github.com/CesiumGS/cesium/issues/12182

It seems these are generated when we run npm run test even with the --release option. I also noticed these would be generated any time we run npm start without --production as the dev server does a build when it starts up.

This PR adds a check for the release flag to skip building for npm run test. It also updates the release guide to specify the dev server should only be started with the --production flag.

One extra precaution we could add is a prepublishOnly lifecycle script to our package.json that calls npm run make-zip right before publish. Would make the publish command slower but guarantee we always build the version of files we want published.

Issue number and link

Fixes https://github.com/CesiumGS/cesium/issues/12182

Testing plan

• Run git clean -dxf to remove all extra files
• Run npm run make-zip like you would during the release
• Run npm run test -- --failTaskOnError --release like in the release guide
• Make sure there are no messages about building and no .map.js files generated

Author checklist

• [ ] I have submitted a Contributor License Agreement
• [ ] I have added my name to CONTRIBUTORS.md
• [ ] I have updated CHANGES.md with a short summary of my change
• [ ] I have added or updated unit tests to ensure consistent code coverage
• [ ] I have updated the inline documentation, and included code examples where relevant
• [ ] I have performed a self-review of my code

[github-actions[bot]]

Thank you for the pull request, @jjspace!

:white_check_mark: We can confirm we have a CLA on file for you.

[ggetz]

Awesome, thanks @jjspace!

One extra precaution we could add is a prepublishOnly lifecycle script to our package.json that calls npm run make-zip right before publish. Would make the publish command slower but guarantee we always build the version of files we want published.

We can follow up about this in a separate thread when appropriate. But the only concern I have with this is that it means the versions of each of the files we just tested will not be the ones that get published. Perhaps a simpler measure would be to add the maps to .npmignore?

[jjspace]

Perhaps a simpler measure would be to add the maps to .npmignore?

The problem with this when coupled with our current build process is that the flow when maps are generated is slightly different than the flow when they are not. If we just ignored the map files it could hide the fact that the files were rebuilt differently than we may want them to be.