base-*: export DEBIAN_FRONTEND=noninteractive

Otherwise Ubuntu 18.04 otherwise prompts for input when installing tzdata.
20 jobs for master in 81 minutes and 50 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Stage0
passed #5823
pull base distributions

00:00:24

 
  Stage1
passed #5828
base:10

00:06:34

passed #5829
base:16.04

00:08:19

passed #5830
base:18.04

00:07:52

passed #5826
base:8

00:05:36

passed #5827
base:9

00:05:52

passed #5824
docker-builder

00:00:55

passed #5825
proxy

00:00:47

 
  Stage2
passed #5831
base:8-backports

00:01:09

passed #5832
dune:2.3

00:00:58

passed #5833
dune:2.4

00:00:38

passed #5834
dune:2.5

00:20:35

passed #5835
dune:2.6

00:15:32

passed #5836
dune:git

00:10:30

 
  Stage3
passed #5837
dune-fufem:2.4

00:03:41

passed #5842
dune-fufem:git

00:03:33

passed #5839
dune-pdelab-deps:2.6

00:02:57

passed #5840
dune-pdelab-deps:git

00:02:09

failed #5838
dune-fufem:git

00:03:00

 
  Publish
passed #5841
publish

00:36:07