This is the script I used
(Updated Version with input from @elquimista from the comments)
#!/bin/bash
ln -fs /usr/share/zoneinfo/America/New_York /etc/localtime
DEBIAN_FRONTEND=noninteractive apt-get install -y tzdata
dpkg-reconfigure --frontend noninteractive tzdata
Seems to work fine.
As one liner:
DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends tzdata