gitlab-ci: drop builds for CentOS 8 (8.1.1911, 8.2.2004, 8.3.2011)

CentOS Linux 8 is long gone. We were only running tests on this old
build environment, to see how we fare in such environment.

The test was broken for 4+ months. Instead of fixing it, disable it.

It's partly caused by RHEL8, as it is somewhat cumbersome to even build
on CentOS 8. That's because some devel packages (like libteam-devel) are
not installable. As workaround for that, we re-build such packages in a
copr ([1]). The problem is, that we only have one copr build for e.g.
CentOS 8. If we rebuild against latest CentOS 8 Stream, then libteam is
build against newer dependencies, which are not installable on CentOS
Linux 8.1.1911 (etc). We would have to build libteam in a way, that
does not drag newer dependencies that are missing on CentOS Linux 8.

For example, trying to use copr [1] on CentOS Linux 8 and installing
"teamd" gives:

  Error:
   Problem: package teamd-devel-1.31-4.el8.x86_64 requires teamd = 1.31-4.el8, but none of the providers can be installed
    - conflicting requests
    - nothing provides libjansson.so.4(libjansson.so.4)(64bit) needed by teamd-1.31-4.el8.x86_64

This could be hacked around, for example by having libteamd-devel not
depend on any teamd package. Instead, just drop it. It's gone.

Arguable, CentOS 8 Stream should be reasonably close (in terms of
versions of gcc, glibc, glib) so we don't miss too much.

[1] https://copr.fedorainfracloud.org/coprs/nmstate/nm-build-deps/

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1793

.gitlab-ci.yml

@@ -57,11 +57,11 @@ variables:
   #
   # This is done by running `ci-fairy generate-template` and possibly bumping
   # ".default_tag".
-  ALPINE_TAG:  'tag-15ad9771f66e'
-  CENTOS_TAG:  'tag-01eb3016c31d'
-  DEBIAN_TAG:  'tag-5b69abc7e7b7'
-  FEDORA_TAG:  'tag-01eb3016c31d'
-  UBUNTU_TAG:  'tag-5b69abc7e7b7'
+  ALPINE_TAG:  'tag-6cb82bbb4f5a'
+  CENTOS_TAG:  'tag-a17a9044f6af'
+  DEBIAN_TAG:  'tag-b6bc6acbb696'
+  FEDORA_TAG:  'tag-a17a9044f6af'
+  UBUNTU_TAG:  'tag-b6bc6acbb696'
 
   ALPINE_EXEC: 'bash .gitlab-ci/alpine-install.sh'
   CENTOS_EXEC: 'bash .gitlab-ci/fedora-install.sh'
@@ -327,28 +327,6 @@ tier3:debian:testing@prep:
     FDO_DISTRIBUTION_EXEC: $DEBIAN_EXEC
   when: manual
 
-tier2:centos:8.1.1911@prep:
-  extends:
-    - .fdo.container-build@centos
-  stage: prep
-  variables:
-    GIT_STRATEGY: none
-    FDO_DISTRIBUTION_VERSION: '8.1.1911'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-    FDO_DISTRIBUTION_EXEC: $CENTOS_EXEC
-  when: manual
-
-tier2:centos:8.3.2011@prep:
-  extends:
-    - .fdo.container-build@centos
-  stage: prep
-  variables:
-    GIT_STRATEGY: none
-    FDO_DISTRIBUTION_VERSION: '8.3.2011'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-    FDO_DISTRIBUTION_EXEC: $CENTOS_EXEC
-  when: manual
-
 tier2:centos:stream8@prep:
   extends:
     - .fdo.container-build@centos
@@ -371,17 +349,6 @@ tier2:centos:stream9@prep:
     FDO_DISTRIBUTION_EXEC: $CENTOS_EXEC
   when: manual
 
-tier3:centos:8.2.2004@prep:
-  extends:
-    - .fdo.container-build@centos
-  stage: prep
-  variables:
-    GIT_STRATEGY: none
-    FDO_DISTRIBUTION_VERSION: '8.2.2004'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-    FDO_DISTRIBUTION_EXEC: $CENTOS_EXEC
-  when: manual
-
 tier2:alpine:latest@prep:
   extends:
     - .fdo.container-build@alpine
@@ -672,30 +639,6 @@ t_debian:testing:
   needs:
     - "tier3:debian:testing@prep"
 
-t_centos:8.1.1911:
-  extends:
-    - .build@template
-    - .fdo.distribution-image@centos
-    - .nm_artifacts_debug
-  stage: tier2
-  variables:
-    FDO_DISTRIBUTION_VERSION: '8.1.1911'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-  needs:
-    - "tier2:centos:8.1.1911@prep"
-
-t_centos:8.3.2011:
-  extends:
-    - .build@template
-    - .fdo.distribution-image@centos
-    - .nm_artifacts_debug
-  stage: tier2
-  variables:
-    FDO_DISTRIBUTION_VERSION: '8.3.2011'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-  needs:
-    - "tier2:centos:8.3.2011@prep"
-
 t_centos:stream8:
   extends:
     - .build@template
@@ -720,18 +663,6 @@ t_centos:stream9:
   needs:
     - "tier2:centos:stream9@prep"
 
-t_centos:8.2.2004:
-  extends:
-    - .build@template
-    - .fdo.distribution-image@centos
-    - .nm_artifacts_debug
-  stage: tier3
-  variables:
-    FDO_DISTRIBUTION_VERSION: '8.2.2004'
-    FDO_DISTRIBUTION_TAG: $CENTOS_TAG
-  needs:
-    - "tier3:centos:8.2.2004@prep"
-
 t_alpine:latest:
   extends:
     - .build@template

.gitlab-ci/config.yml

@@ -61,14 +61,8 @@ distributions:
   - name: centos
     tier: 2
     versions:
-      - '8.1.1911'
-      - '8.3.2011'
       - 'stream8'
       - 'stream9'
-  - name: centos
-    tier: 3
-    versions:
-      - '8.2.2004'
   - name: alpine
     tier: 2
     versions:

.gitlab-ci/fedora-install.sh

@@ -8,9 +8,7 @@ CENTOS_VERSION=0
 grep -q '^NAME=.*\(CentOS\)' /etc/os-release && IS_CENTOS=1
 grep -q '^NAME=.*\(Fedora\)' /etc/os-release && IS_FEDORA=1
 if [ $IS_CENTOS = 1 ]; then
-    if grep -q '^VERSION_ID=.*\<7\>' /etc/os-release ; then
-        CENTOS_VERSION=7
-    elif grep -q '^VERSION_ID=.*\<8\>' /etc/os-release ; then
+    if grep -q '^VERSION_ID=.*\<8\>' /etc/os-release ; then
         CENTOS_VERSION=8
     elif grep -q '^VERSION_ID=.*\<9\>' /etc/os-release ; then
         CENTOS_VERSION=9
@@ -23,19 +21,7 @@ if [ $IS_CENTOS = 1 ]; then
 fi
 
  if [ "$IS_CENTOS" = 1 ]; then
-    if [ "$CENTOS_VERSION" = 7 ]; then
-        yum install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
-        yum install -y glibc-common
-        localedef -c -i pl_PL -f UTF-8 pl_PL.UTF-8
-        locale -a
-        yum install -y python36-dbus python36-gobject-base
-    elif [ "$CENTOS_VERSION" = 8 -o "$CENTOS_VERSION" = stream8 ]; then
-        if [ "$CENTOS_VERSION" = 8 ]; then
-            # CentOS Linux 8 is now EOF and plain `dnf upgrade` does not work. We need
-            # to patch the mirror list.
-            sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*
-            sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*
-        fi
+    if [ "$CENTOS_VERSION" = stream8 ]; then
         dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
         dnf install -y 'dnf-command(config-manager)'
         dnf config-manager --set-enabled powertools || \