Update docker to use directly pandoc download

Additionally update docker with some  install and cleanup best practices

.docker/resume.dockerfile

@@ -6,8 +6,18 @@ RUN useradd --user-group --create-home --shell /bin/false app
 ENV HOME=/home/app
 WORKDIR $HOME
 
-RUN apt-get update
-RUN apt-get install build-essential pandoc context -y
+RUN apt-get update && \
+    apt-get install -y \
+    build-essential \
+    wget \
+    context \
+    && rm -rf /var/lib/apt/lists/*
+RUN wget https://github.com/jgm/pandoc/releases/download/2.2.1/pandoc-2.2.1-1-amd64.deb
+RUN dpkg -i pandoc-2.2.1-1-amd64.deb  && rm pandoc-*.deb
+#Cleanup to reduce container size
+RUN apt-get remove -y wget && \ 
+    apt-get autoclean && \
+    apt-get clean
 
 ENV APP_NAME=resume