This commit reverts the key of Web field in ipn.ServiceConfig to use FQDN instead of service
name for the host part of HostPort. This change is because k8s operator already build base on
the assumption of the part being FQDN. We don't want to break the code with dependency.
Fixestailscale/corp#30695
Signed-off-by: KevinLiang10 <37811973+KevinLiang10@users.noreply.github.com>