Add release verification to pulumi-command

[mjeffryes]

Our workflows for bridged and component providers have a step for downloading and running a test against a released provider SDK at the end of the release workflow. We just have to configure a test for each repo to run on release. (It can be a very basic test as the only goal is to check for existence and basic function of the released provider binary and SDK.)

Example from azure:

releaseVerification:
  nodejs: examples/topic
  python: examples/eventhub-py
  dotnet: examples/appservice-cs
  go: examples/network-go