[Feature Request] Ensure all samples can be fully built, run and validated in automated way

[mjameswh]

What

Add a script on each sample that perform a completely automated validation of that sample.

Why

High quality samples are essential to allow users to learn and start using Temporal. Unfortunately, from time to time, some sample stops working. Common situations leading to sample failure are dependencies getting updated in incompatible ways, and Temporal SDK itself introducing breaking changes.

At the moment, testing samples is unreasonably time consuming, notably because samples doesn't all follow the same execution semantic (most are using npm run start and npm run workflow, but ~25% require different steps), some require particular environment (eg. Mongo), and because "success" is not always obvious.