Add apt-get update back

Author: shahmishal

5.2/ubuntu/16.04/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:16.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL Description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     libatomic1 \
     libcurl3 \

5.2/ubuntu/16.04/slim/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:16.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL Description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     libatomic1 \
     libcurl3 \

5.2/ubuntu/18.04/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:18.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL Description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     libatomic1 \
     libcurl4 \

5.2/ubuntu/18.04/slim/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:18.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL Description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     libatomic1 \
     libcurl4 \

5.2/ubuntu/20.04/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:20.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     binutils \
     git \

5.2/ubuntu/20.04/slim/Dockerfile

@@ -2,7 +2,7 @@ FROM ubuntu:20.04
 LABEL maintainer="Swift Infrastructure <[email protected]>"
 LABEL description="Docker Container for the Swift programming language"
 
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
+RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -q update && \
     apt-get -q install -y \
     libcurl4 \
     libxml2 \