Add land bot dependencies to base image setup script

Summary: See title.

Test Plan:

./build-containers/build.sh -r reg-staging.bitframe.org -c ~/projects/bitcoin-abc -f ./contrib -s ./teamcity/setup-debian-buster.sh -t abc-land-bot debian:buster ""

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D6265