Bumps wireguard-go pin to include the roaming endpoints fix, and
two internal enhancements.
Pulls stock wireguard-go for non-tailscale simulation in tests,
to use its endpoint discovery mechanism.
Updates #20082
Change-Id: I2ff282cb7fe4ab099ce5e780a1d40ae86a6a6964
Signed-off-by: Alex Valiushko <alexvaliushko@tailscale.com>