tailcfg, control/controlclient: add PingRequest.URLIsNoise [capver 38]

Change-Id: I19bb63b6d99e96b2f9fd2c440afcc31d38137ded
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f