Pipeline testing improvements

[c-ryan-k]

• Allows release pipeline to continue to a staged release even if ITs are failing

• Now, failing IT jobs will show as SucceededWithIssues - and can be re-run or investigated so that a flaky integration test will not stop a release.
  

• Moves install/version-check task to build stage

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Thank you for contributing to the IoT extension!

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General Guidelines

• If introducing new functionality or modified behavior, are they backed by unit and integration tests?
• In the same context as above are command names and their parameter definitions accurate? Do help docs have sufficient content?
• Have all unit and integration tests passed locally? i.e. pytest <project root> -vv
• Have static checks passed using the .pylintrc and .flake8 rules? Look at the CI scripts for example usage.
• Have you made an entry in HISTORY.rst which concisely explains your feature or change?