Você pode, mas esteja avisado de que o aviso está lá para protegê-lo - não o ignore de ânimo leve.
De man apt-get
:
-y, --yes, --assume-yes
Automatic yes to prompts; assume "yes" as answer to all prompts and
run non-interactively. If an undesirable situation, such as
changing a held package, trying to install a unauthenticated
package or removing an essential package occurs then apt-get will
abort. Configuration Item: APT::Get::Assume-Yes.