automation: always install docker-ce

Docker has published packages for Ubuntu Disco and we no longer
need this one-off.

Differential Revision: https://phab.mercurial-scm.org/D6911

contrib/automation/hgautomation/linux.py

@@ -219,6 +219,7 b' PACKAGES="\\'
     darcs \
     debhelper \
     devscripts \
+    docker-ce \
     dpkg-dev \
     dstat \
     emacs \
@@ -282,12 +283,6 b' if [ "$LSB_RELEASE" != "disco" ]; then'
     PACKAGES="$PACKAGES monotone"
 fi
 
-# As of April 27, 2019, Docker hasn't published packages for
-# Ubuntu 19.04 yet.
-if [ "$LSB_RELEASE" != "disco" ]; then
-    PACKAGES="$PACKAGES docker-ce"
-fi
-
 sudo DEBIAN_FRONTEND=noninteractive apt-get -yq install --no-install-recommends $PACKAGES
 
 # Create clang-format symlink so test harness finds it.