Add test for install process on windows/osx/linux

[kamilogorek]

So things like https://github.com/getsentry/sentry-cli/pull/1151 + https://github.com/getsentry/sentry-cli/pull/1155 won't happen again.

[github-actions[bot]]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀