Remove object files and other large not needed artifacts from prebuilds.

[btsimonh]

Thanks for contributing!

• Have you updated CHANGELOG.md? - no there is none for prebuilds?

Removes LARGE artifacts in the prebuilds.

Macos:

deletes object files (save a few mb)

Linux:

deletes object files and strips libraries (save ~22mbytes)

Windows

Deletes object files and debug files. (save 45mbytes)

[chearon]

Thank you, I've been meaning to do this. I have a few other ideas on how to get the size down even more and hopefully fit it in the NPM tarball. Hoping to look at your other PRs this weekend.