Don't call node-gyp anymore (#120673)

This npx call was installing node-gyp 8.0 which requires a newer version of Python then what's in our containers.

I've removed it but also followed the advice of the comment that says only remove it if prebuild-install is updated in keytar...

So I updated keytar's dependencies which pulled in prebuild-install 6.1.1 with the fix.

If this isn't the right move, feel free to revert and then we can move to Debian Buster which has a version of Python that is new enough.