Degrade gracefully when uploading debug symbols if sentry is unreachable

[marandaneto]

Related to getsentry/team-mobile#3

Implementation detail: getsentry/team-mobile#3 (comment)

[github-actions]

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 🥀