update Dockerfile to install the runtime ssl lib

Dockerfile

@@ -1,15 +1,24 @@
-FROM rust:1.73-buster
+# we need the same debian version on the rust and varnish so
+# that libssl-dev and libssl3 match
+FROM rust:1.73-bookworm
 
 WORKDIR /vmod_reqwest
 ARG VMOD_REQWEST_VERSION=0.0.10
 ARG RELEASE_URL=https://github.com/gquintard/vmod_reqwest/archive/refs/tags/v${VMOD_REQWEST_VERSION}.tar.gz
 ENV CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse
 
-RUN curl -s https://packagecloud.io/install/repositories/varnishcache/varnish74/script.deb.sh | bash && apt-get update && apt-get install -y varnish-dev clang libssl-dev
-
-RUN curl -Lo dist.tar.gz ${RELEASE_URL} && \
-	tar xavf dist.tar.gz --strip-components=1 && \
+RUN set -e; \
+	curl -s https://packagecloud.io/install/repositories/varnishcache/varnish74/script.deb.sh | bash; \
+	apt-get install -y varnish-dev clang libssl-dev; \
+	curl -Lo dist.tar.gz ${RELEASE_URL}; \
+	tar xavf dist.tar.gz --strip-components=1; \
 	cargo build --release
 
 FROM varnish:7.4
+USER root
+RUN set -e; \
+	apt-get update; \
+	apt-get install -y libssl3; \
+	rm -rf /var/lib/apt/lists/*
 COPY --from=0 /vmod_reqwest/target/release/libvmod_reqwest.so /usr/lib/varnish/vmods/
+USER varnish