ci: Drop dalmatian testing

It is unmaintained [1].

[1] https://releases.openstack.org/

Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

Author: stephenfin

.github/workflows/with-defaults.yml

@@ -1,3 +1,4 @@
+---
 name: with-defaults
 on:
   pull_request:
@@ -25,12 +26,6 @@ jobs:
           - name: "epoxy-22.04"
             openstack_version: "stable/2025.1"
             ubuntu_version: "22.04"
-          - name: "dalmatian-24.04"
-            openstack_version: "stable/2024.2"
-            ubuntu_version: "24.04"
-          - name: "dalmatian-22.04"
-            openstack_version: "stable/2024.2"
-            ubuntu_version: "22.04"
     runs-on: ubuntu-${{ matrix.ubuntu_version }}
     name: A job to deploy devstack with defaults
     steps: