gitlab-ci: enable tests on Fedora 40

We don't use "rawhide", because we explicitly enable Fedora versions by
their release number (and "rawhide" is just an alias).

However, by now "rawhide" is Fedora 40. Enable it.

.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-d53edbf2ebdd'
+  ALPINE_TAG:  'tag-d831870051be'
-  CENTOS_TAG:  'tag-c374af7add25'
+  CENTOS_TAG:  'tag-62b1e9c63f3f'
-  DEBIAN_TAG:  'tag-0e28ea47158f'
+  DEBIAN_TAG:  'tag-c531494bb725'
-  FEDORA_TAG:  'tag-c374af7add25'
+  FEDORA_TAG:  'tag-62b1e9c63f3f'
-  UBUNTU_TAG:  'tag-0e28ea47158f'
+  UBUNTU_TAG:  'tag-c531494bb725'
 
   ALPINE_EXEC: 'bash .gitlab-ci/alpine-install.sh'
   CENTOS_EXEC: 'bash .gitlab-ci/fedora-install.sh'
@@ -129,6 +129,17 @@ tier2:fedora:39@prep:
     FDO_DISTRIBUTION_EXEC: $FEDORA_EXEC
   when: manual
 
+tier2:fedora:40@prep:
+  extends:
+    - .fdo.container-build@fedora
+  stage: prep
+  variables:
+    GIT_STRATEGY: none
+    FDO_DISTRIBUTION_VERSION: '40'
+    FDO_DISTRIBUTION_TAG: $FEDORA_TAG
+    FDO_DISTRIBUTION_EXEC: $FEDORA_EXEC
+  when: manual
+
 tier3:fedora:30@prep:
   extends:
     - .fdo.container-build@fedora
@@ -500,6 +511,18 @@ t_fedora:39:
   needs:
     - "tier2:fedora:39@prep"
 
+t_fedora:40:
+  extends:
+    - .build@template
+    - .fdo.distribution-image@fedora
+    - .nm_artifacts_debug
+  stage: tier2
+  variables:
+    FDO_DISTRIBUTION_VERSION: '40'
+    FDO_DISTRIBUTION_TAG: $FEDORA_TAG
+  needs:
+    - "tier2:fedora:40@prep"
+
 t_fedora:30:
   extends:
     - .build@template

.gitlab-ci/config.yml

@@ -28,6 +28,7 @@ distributions:
     versions:
       - '37'
       - '39'
+      - '40'
   - name: fedora
     tier: 3
     versions: