ci: bump EOL Fedora versions to 42/43 (#13206)

Fedora 39 (EOL 2024-11-26), Fedora 40 (EOL 2025-05-13), and Fedora 41
(EOL 2025-12-15) are all out of support and no longer receive security
updates. This bumps the kubevirt CI test matrix to currently supported
releases, distributing tests across Fedora 42 (supported until
2026-05-13) and Fedora 43 (supported until 2026-12-09) to keep
multi-version coverage.

- Add fedora-43 image entry to the kubevirt image-builder
- Rename fedora39-* tests to fedora43-* (4 tests)
- Rename fedora40-* tests to fedora43-* (2 tests)
- Rename fedora41-* tests to fedora42-* (4 tests)
- Update .gitlab-ci/kubevirt.yml testcase names
- Regenerate docs/developers/ci.md

All 10 existing Fedora test configurations (kube-router, calico-selinux,
calico-swap-selinux, crio with/without SELinux enforcing, docker-calico,
flannel-crio-collection-scale) are preserved.

Signed-off-by: Kay Yan <kay.yan@daocloud.io>

.gitlab-ci/kubevirt.yml

@@ -40,8 +40,8 @@ pr:
           - debian11-macvlan
           - debian12-cilium
           - debian13-cilium
-          - fedora39-kube-router
-          - fedora41-kube-router
+          - fedora42-kube-router
+          - fedora43-kube-router
           - fedora42-calico
           - rockylinux9-cilium
           - rockylinux10-cilium
@@ -56,7 +56,7 @@ pr:
           - ubuntu24-kube-router-sep
           - ubuntu24-kube-router-svc-proxy
           - ubuntu24-ha-separate-etcd
-          - fedora40-flannel-crio-collection-scale
+          - fedora43-flannel-crio-collection-scale
 
 # This is for flakey test so they don't disrupt the PR worklflow too much.
 # Jobs here MUST have a open issue so we don't lose sight of them
@@ -105,10 +105,10 @@ pr_full:
           - debian11-custom-cni
           - debian11-kubelet-csr-approver
           - debian12-custom-cni-helm
-          - fedora39-calico-swap-selinux
-          - fedora39-crio
-          - fedora41-calico-swap-selinux
-          - fedora41-crio
+          - fedora42-calico-swap-selinux
+          - fedora42-crio
+          - fedora43-calico-swap-selinux
+          - fedora43-crio
           - ubuntu24-calico-ha-wireguard
           - ubuntu24-flannel-ha
           - ubuntu24-flannel-ha-once
@@ -166,9 +166,9 @@ periodic:
           - debian11-calico-upgrade
           - debian11-calico-upgrade-once
           - debian12-cilium-svc-proxy
-          - fedora39-calico-selinux
-          - fedora40-docker-calico
-          - fedora41-calico-selinux
+          - fedora42-calico-selinux
+          - fedora43-calico-selinux
+          - fedora43-docker-calico
           - ubuntu24-calico-etcd-kubeadm-upgrade-ha
           - ubuntu24-calico-ha-recover
           - ubuntu24-calico-ha-recover-noquorum