Combine all apt-get commands to really delete the cache from all layers

ci/release-image/Dockerfile

@@ -1,10 +1,21 @@
 FROM debian:10
 
-RUN apt-get update
-RUN apt-get install -y curl
+RUN apt-get update \
+ && apt-get install -y \
+    curl \
+    dumb-init \
+    htop \
+    locales \
+    man \
+    nano \
+    git \
+    procps \
+    ssh \
+    sudo \
+    vim \
+  && rm -rf /var/lib/apt/lists/*
 
 # https://wiki.debian.org/Locale#Manually
-RUN apt-get install -y locales
 RUN sed -i "s/# en_US.UTF-8/en_US.UTF-8/" /etc/locale.gen
 RUN locale-gen
 ENV LANG=en_US.UTF-8
@@ -12,9 +23,6 @@ ENV LANG=en_US.UTF-8
 RUN chsh -s /bin/bash
 ENV SHELL=/bin/bash
 
-RUN apt-get install -y dumb-init sudo
-RUN apt-get install -y man procps vim nano htop ssh git
-
 RUN adduser --gecos '' --disabled-password coder && \
   echo "coder ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers.d/nopasswd
 
@@ -24,8 +32,6 @@ RUN curl -SsL https://github.com/boxboat/fixuid/releases/download/v0.4/fixuid-0.
     mkdir -p /etc/fixuid && \
     printf "user: coder\ngroup: coder\n" > /etc/fixuid/config.yml
 
-RUN rm -rf /var/lib/apt/lists/*
-
 COPY release/code-server*.tar.gz /tmp/
 RUN cd /tmp && tar -xzf code-server*.tar.gz && rm code-server*.tar.gz && \
   mv code-server* /usr/local/lib/code-server && \