shared/version: Fix regression in useragent string
shared/version: Fix regression in useragent string

A recent change to the user-agent logic caused the architecture to get
incorrectly capitalized and for the OS name to be dropped.

Signed-off-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>

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