[Merge] ~puida/ubuntu-release-upgrader:rabbitmq-upgrade-resolute into ubuntu-release-upgrader:ubuntu/main

[Guilherme Puida Moreira]

Thanks, Julian.

I added exception handling to the subprocess.run and json.loads calls so if they fail the user sees a nicer-looking error message. I considered adding details about the exception caught in the error message itself, but I thought this was overkill (and it is already being logged to the usual log file).

Also slightly tweaked the error text.
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https://code.launchpad.net/~puida/ubuntu-release-upgrader/+git/ubuntu-release-upgrader/+merge/500687
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