ci: Add workflows for build, test, and release actions

[c-ryan-k]

This also stages tox.ini for running integration tests pipelines locally the same way we'll eventually run them in a pipeline.

While I smooth out the integration test connection between ADO and github, this PR will at least get most of the engineering infrastructure setup for builds and releases.

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[c-ryan-k]

For test runs please see recent runs for CI, Tox tests, and Release here: https://github.com/c-ryan-k/azure-iot-cli-extension/actions

Before merging, we'll need to update the new hosted pools to point to this repo rather than my fork.