Update Dockerfile

Dockerfile

@@ -15,7 +15,6 @@ RUN apt-get update \
   && apt-get install -y wget gnupg2 lsb-core apt-transport-https ca-certificates curl \
   && wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add - \
   && echo "deb [ trusted=yes ] https://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" | tee /etc/apt/sources.list.d/pgdg.list \
-  && curl http://repo.varnish-cache.org/debian/GPG-key.txt | sudo apt-key add -
   && wget --quiet -O - https://deb.nodesource.com/setup_16.x | bash - \
   && apt-get update \
   && apt-get install -y nodejs
@@ -79,6 +78,7 @@ RUN apt-get install -y --no-install-recommends \
   tar \
   ttf-unifont \
   unzip \
+  varnish \
   wget \
   zlib1g-dev \
 && apt-get clean autoclean \