--auth is already best-effort, but we saw some CI failures due to
failing to fetch stats when cigocached was overwhelmed recently. Make
sure it fails more gracefully in the absence of cigocached like the rest
of cigocacher already does.
Updates tailscale/corp#37059
Change-Id: I0703b30b1c5a7f8c649879a87e6bcd2278610208
Signed-off-by: Tom Proctor <tomhjp@users.noreply.github.com>
7fb61e1765