Signal AppImage docker builder

Dockerfile

FROM node:16.13.0
RUN export DEBIAN_FRONTEND=noninteractive
RUN apt-get update -yqq && apt-get full-upgrade -yqq
RUN apt-get install -yqq curl wget git jq git-lfs
RUN git clone https://github.com/signalapp/Signal-Desktop /opt/project
WORKDIR /opt/project
RUN git checkout $(git describe --tags $(git rev-list --tags --max-count=100) | grep -v beta | head -n 1)
RUN cat package.json | jq '.build.linux += {target:["AppImage"]}' > with_appimage_package.json
RUN mv with_appimage_package.json package.json
RUN yarn install
RUN yarn build-release
RUN ls -la ./release