ci: upgrade FreeBSD from 14.2 to 14.3 (#7758)

14.2 is no more available:

```
$ gcloud compute images list --project freebsd-org-cloud-dev --no-standard-images
NAME                                             PROJECT                FAMILY                       DEPRECATED  STATUS
freebsd-13-5-release-amd64-gce                   freebsd-org-cloud-dev  freebsd-13-5                             READY
freebsd-13-5-stable-amd64-v20251030              freebsd-org-cloud-dev  freebsd-13-5-snap                        READY
freebsd-13-5-stable-amd64-v20251107              freebsd-org-cloud-dev  freebsd-13-5-snap                        READY
freebsd-14-3-release-amd64-ufs-gce               freebsd-org-cloud-dev  freebsd-14-3                             READY
freebsd-14-3-stable-amd64-ufs-20251120           freebsd-org-cloud-dev  freebsd-14-3-snap                        READY
freebsd-14-3-stable-amd64-ufs-20251127           freebsd-org-cloud-dev  freebsd-14-3-snap                        READY
freebsd-14-3-stable-amd64-zfs-20251113           freebsd-org-cloud-dev  freebsd-14-3-snap                        READY
freebsd-14-3-stable-amd64-zfs-20251120           freebsd-org-cloud-dev  freebsd-14-3-snap                        READY
freebsd-14-3-stable-amd64-zfs-20251127           freebsd-org-cloud-dev  freebsd-14-3-snap                        READY
freebsd-15-0-release-amd64-ufs                   freebsd-org-cloud-dev  freebsd-15-0-amd64-ufs                   READY
freebsd-15-0-release-amd64-zfs                   freebsd-org-cloud-dev  freebsd-15-0-amd64-zfs                   READY
freebsd-15-0-stable-amd64-ufs-20251120           freebsd-org-cloud-dev  freebsd-15-0-amd64-ufs-snap              READY
freebsd-15-0-stable-amd64-ufs-20251127           freebsd-org-cloud-dev  freebsd-15-0-amd64-ufs-snap              READY
freebsd-15-0-stable-amd64-zfs-20251120           freebsd-org-cloud-dev  freebsd-15-0-amd64-zfs-snap              READY
freebsd-15-0-stable-amd64-zfs-20251127           freebsd-org-cloud-dev  freebsd-15-0-amd64-zfs-snap              READY
freebsd-16-0-current-amd64-ufs-20251110          freebsd-org-cloud-dev  freebsd-16-0-snap                        READY
freebsd-16-0-current-amd64-zfs-20251110          freebsd-org-cloud-dev  freebsd-16-0-snap                        READY
freebsd-16-0-current-arm64-aarch64-ufs-20251111  freebsd-org-cloud-dev  freebsd-16-0-snap                        READY
freebsd-16-0-current-arm64-aarch64-zfs-20251111  freebsd-org-cloud-dev  freebsd-16-0-snap                        READY
```

(cherry picked from commit 5471a58)

Author: martin-g

.cirrus.yml

@@ -1,7 +1,7 @@
 only_if: $CIRRUS_TAG == '' && ($CIRRUS_PR != '' || $CIRRUS_BRANCH == 'master' || $CIRRUS_BRANCH =~ 'tokio-.*')
 auto_cancellation: $CIRRUS_BRANCH != 'master' && $CIRRUS_BRANCH !=~ 'tokio-.*'
 freebsd_instance:
-  image_family: freebsd-14-2
+  image_family: freebsd-14-3
 env:
   RUST_STABLE: stable
   RUST_NIGHTLY: nightly-2024-05-05