[Merge] ~lamoura/update-notifier:update-esm-handling into update-notifier:master

[Lucas Albuquerque Medeiros de Moura]

Hi Brian, thank you for the review on that. And the reason that I have not used python3-distro-info is just because I just recently discovered that it existed. But I have updated the code to use it. Thanks for pointing that out.

Also, this change also address the diff comment you made
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https://code.launchpad.net/~lamoura/update-notifier/+git/update-notifier/+merge/401002
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