Support REPO_SUFFIX environment variable

It allows using something other than $DISTRO_VERSION as the last
component of the repository name before the tag. This gives more
flexibility for organizing large collections of images e.g. for
different architectures / purposes.

See e.g. mesa/mesa!2722
48 jobs for REPO_SUFFIX in 39 minutes and 7 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Bootstrapping
passed #947676
bootstrap

00:01:48

passed #947677
aarch64
bootstrap@arm64v8

00:02:19

 
  Alpine Container Build
passed #947680
alpine-forced:latest@container-ifnot-exists

00:00:52

passed #947678
alpine:latest@container-build

00:01:02

passed #947679
aarch64
alpine:latest@container-build@arm64v8

00:00:45

 
  Alpine Check
passed #947683
alpine-forced-ifnot-exists:latest@check

00:00:22

passed #947681
alpine:latest@check

00:00:18

passed #947682
aarch64
alpine:latest@@check@arm64v8

00:00:15

passed #947684
alpine:latest@container-ifnot-exists

00:00:20

 
  Arch Container Build
passed #947685
arch@container-build

00:02:12

passed #947686
arch-forced@container-ifnot-exists

00:02:04

 
  Arch Check
passed #947687
arch@check

00:00:20

passed #947689
arch@container-ifnot-exists

00:00:18

passed #947688
arch-forced-ifnot-exists@check

00:00:22

 
  Centos Container Build
passed #947690
centos:7@container-build

00:01:32

passed #947691
centos:8@container-build

00:01:32

passed #947692
centos-forced:8@container-ifnot-exists

00:01:15

 
  Centos Check
passed #947693
centos:7@check

00:00:17

passed #947694
centos:8@check

00:00:18

passed #947696
centos:8@container-ifnot-exists

00:00:12

passed #947695
centos-forced-ifnot-exists:8@check

00:00:13

 
  Ubuntu Container Build
passed #947700
ubuntu:18.04@container-build

00:01:09

passed #947697
ubuntu:18.10@container-build

00:01:10

passed #947698
aarch64
ubuntu:18.10@container-build@arm64v8

00:01:46

passed #947699
ubuntu-forced:18.10@container-ifnot-exists

00:01:25

 
  Ubuntu Check
passed #947705
ubuntu:18.04@check

00:00:40

passed #947701
ubuntu:18.10@check

00:00:16

passed #947702
aarch64
ubuntu:18.10@check@arm64v8

00:00:15

passed #947704
ubuntu:18.10@container-ifnot-exists

00:00:46

passed #947703
ubuntu:forced-ifnot-exists@check

00:00:36

 
  Debian Container Build
passed #947709
debian:buster@container-build

00:01:12

passed #947708
debian-forced:stretch@container-ifnot-exists

00:01:15

passed #947706
debian:stretch@container-build

00:01:26

passed #947707
aarch64
debian:stretch@container-build@arm64v8

00:01:05

 
  Debian Check
passed #947714
debian:buster@check

00:00:21

passed #947712
debian:forced-ifnot-exists@check

00:00:14

passed #947710
debian:stretch@check

00:00:22

passed #947711
aarch64
debian:stretch@check@arm64v8

00:00:34

passed #947713
debian:stretch@container-ifnot-exists

00:00:21

 
  Fedora Container Build
passed #947715
fedora:29@container-build

00:02:23

passed #947717
aarch64
fedora:30@container-build@arm64v8

00:02:46

passed #947718
fedora-forced:rawhide@container-ifnot-exists

00:02:15

passed #947716
fedora:rawhide@container-build

00:02:19

 
  Fedora Check
passed #947719
fedora:29@check

00:00:29

passed #947721
aarch64
fedora:30@check@arm64v8

00:00:20

passed #947722
fedora-forced-ifnot-exists:rawhide@check

00:00:31

passed #947720
fedora:rawhide@check

00:00:37

passed #947723
fedora:rawhide@container-ifnot-exists

00:00:19