Comment 1 for bug 1954842

Confirmed on your suggested approach. Even services which don't have prompts will allow you to passe --assume-yes without error. It is ok to provide this param to all enable calls.
$ ua enable cis --assume-yes
One moment, checking your subscription first
Updating package lists
Installing CIS Audit packages
CIS Audit enabled
Visit https://security-certs.docs.ubuntu.com/en/cis to learn how to use CIS
$ echo $?
0