simplify the action to just use the pre-built mdbook image

Dockerfile

@@ -1,44 +1,10 @@
 # Container image that runs your code
-FROM rust:1.66.1-slim
-
-# Version numbers for all the crates we're going to install
-ARG MDBOOK_VERSION="0.4.25"
-ARG MDBOOK_LINKCHECK_VERSION="0.7.7"
-
-ARG MDBOOK_TOC_VERSION="0.7.0"
-ARG MDBOOK_OPEN_ON_GH_VERSION="2.3.1"
-ARG MDBOOK_KROKI_VERSION="0.1.2"
-ARG MDBOOK_REGEX_VERSION="0.0.2"
-ARG MDBOOK_ADMONISH_VERSION="1.8.0"
-ARG MDBOOK_TOC_VERSION="0.11.0"
-
-ENV CARGO_INSTALL_ROOT /usr/local/
-ENV CARGO_TARGET_DIR /tmp/target/
-
-RUN apt-get update && \
-    apt-get install -y libssl-dev pkg-config ca-certificates build-essential make perl gcc libc6-dev
-
-RUN cargo install mdbook --vers ${MDBOOK_VERSION} --verbose
-RUN cargo install mdbook-linkcheck --vers ${MDBOOK_LINKCHECK_VERSION} --verbose
-RUN cargo install mdbook-kroki-preprocessor --vers ${MDBOOK_KROKI_VERSION} --verbose
-RUN cargo install mdbook-toc --vers ${MDBOOK_TOC_VERSION} --verbose
-RUN cargo install mdbook-open-on-gh --vers ${MDBOOK_OPEN_ON_GH_VERSION} --verbose
-RUN cargo install mdbook-regex --vers ${MDBOOK_REGEX_VERSION} --verbose
-RUN cargo install mdbook-admonish --vers ${MDBOOK_ADMONISH_VERSION} --verbose
-
-# Create the final image
-FROM ubuntu:20.04
+FROM ghcr.io/input-output-hk/catalyst-gh-mdbook-doc:main
 
 LABEL maintainer="[email protected]"
 ENV RUST_LOG info
 
 # used when serving
 EXPOSE 3000
 
-COPY --from=build /usr/local/bin/mdbook* /bin/
-
-# Make sure we have certs
-RUN apt-get update && apt-get install --no-install-recommends -y ca-certificates && rm -rf /var/cache/apt/lists
-
-
 ENTRYPOINT [ "/bin/mdbook" ]