Pins wireguard-go to tailscale/wireguard-go@3aa5c94,
a standalone branch release-1.100 with the cherry-picked patch.
This is to avoid merging two additional features on which the
roaming endpoints fix sits. release-1.100 branch omits them and
differs from the previous prod wireguard-go only by the fix.
Not to be merged in main, a mirror PR is created that pins main to all
new changes including the fix.
Pulls stock wireguard-go for non-tailscale simulation in tests,
to use its endpoint discovery mechanism.
Updates #20082
Change-Id: I8055a70d87382db18f60a11e811b2b896a6a6964
Signed-off-by: Alex Valiushko <[email protected]>