tests: move common cloud-init config to a unified file, rename some base distribution.

tests/cloud-init/debian12-kde.user-data.yml

@@ -0,0 +1,31 @@
+#cloud-config
+
+packages:
+  - apparmor-profiles
+  - auditd
+  - build-essential
+  - config-package-dev
+  - debhelper
+  - devscripts
+  - htop
+  - qemu-guest-agent
+  - rsync
+  - spice-vdagent
+  - vim
+  - task-kde-desktop
+
+runcmd:
+  - apt-get update -y
+  - apt-get install -y -t bookworm-backports golang-go
+
+write_files:
+  # Add backports repository
+  - path: /etc/apt/sources.list
+    append: true
+    content: deb http://deb.debian.org/debian bookworm-backports main contrib non-free
+
+  # Setup shared directory
+  - path: /etc/fstab
+    append: true
+    content: |
+      0a31bc478ef8e2461a4b1cc10a24cc4 /home/user/Projects/apparmor.d  virtiofs defaults  0  1