[engsys] Add template-based package.json for Azure emitters

[xirzec]

Currently we have to update the emitters each time we change dependencies or npm scripts, which can create a lag where emitter PRs will still be using the previous package.json values and potentially be unable to build.

The proposal here is to figure out a way to have the emitter pull in a template that lives in this repo which will be kept up to date as we make these kinds of changes to existing packages.