update Dockerfile

docs/Dockerfile

@@ -0,0 +1,17 @@
+FROM node:16-slim AS nodejs-base
+RUN apt-get -q update && \
+    env DEBIAN_FRONTEND=noninteractive apt-get -y install git && \
+    apt-get clean && rm -fr /var/lib/apt/lists/*
+
+FROM nodejs-base AS build
+RUN yarnpkg global add --network-timeout 1000000000 --latest --production --silent https://gancio.org/latest.tgz && \
+    apt-get clean && rm -fr /var/lib/apt/lists/* && \
+    yarnpkg cache clean
+
+FROM nodejs-base
+COPY --from=build /usr/local/share/.config/yarn/ /usr/local/share/.config/yarn/
+RUN ln -s ../share/.config/yarn/global/node_modules/.bin/gancio /usr/local/bin/gancio
+
+ENTRYPOINT ["/usr/local/bin/gancio"]
+
+