Adding a root key that signs the current signing key on
pkgs.tailscale.com. This key is here purely for development and should
be replaced before 1.50 release.
Updates #8760
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
To make key management less error-prone, use different PEM block types
for root and signing keys. As a result, separate out most of the Go code
between root/signing keys too.
Updates #8760
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>