cmd/tailscaled: log Windows service change requests

And add a little comment.

Change-Id: If0bedf8aefd8d528149548fba829e7a9a8b2e114
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