net/netcheck: lower the hairpin check timeout to 100ms.
This single check is the long pole for netcheck, and significantly slows down magicsock
tests.
stunProbeTimeout = 3 * time.Second
// hairpinCheckTimeout is the amount of time we wait for a
// hairpinned packet to come back.
- hairpinCheckTimeout = 500 * time.Millisecond
+ hairpinCheckTimeout = 100 * time.Millisecond
// defaultActiveRetransmitTime is the retransmit interval we use
// for STUN probes when we're in steady state (not in start-up),
// but don't have previous latency information for a DERP
