Ensure Deploy with Pulumi buttons work for all examples

[lukehoban]

Many/most examples have a "Deploy with Pulumi" button on their README page. Many of these are not correctly configured though, and don't fully work - due to missing configuration options and/or configuration not being listed in the Pulumi.yaml file for UI-driven configuration.

We should audit all examples which use the button, and ideally ensure there is some automated validation to ensure these continue working.