Merge branch 'add-apt-cleanup' into 'master'

Clean up apt lists to reduce the Docker image size

Signed-off-by: Tao Wang <twang2218@gmail.com>

See merge request !1129

CHANGELOG.md

@@ -6,6 +6,7 @@ omnibus-gitlab repository.
 8.15.0
 
 - Update git to 2.8.4
+- Clean up apt lists to reduce the Docker image size
 
 8.14.0
 

docker/assets/setup

@@ -10,6 +10,7 @@ echo "deb https://packages.gitlab.com/gitlab/${PACKAGECLOUD_REPO}/ubuntu/ ${DIST
 wget -q -O - https://packages.gitlab.com/gpg.key | apt-key add -
 apt-get update
 apt-get install -yq --no-install-recommends ${RELEASE_PACKAGE}=${RELEASE_VERSION}
+rm -rf /var/lib/apt/lists/*
 
 # Create sshd daemon
 mkdir -p /opt/gitlab/sv/sshd/supervise /opt/gitlab/sv/sshd/log/supervise