[packer] Manually install ansible 7.x via pip

ansible-core 2.15 is breaking the playbook. Keep the previous version until
things are sorted out.

packer/clean.sh

@@ -1,8 +1,7 @@
 #!/bin/sh
 
-set -e
+set -ex
 
-pacman -Rs --noconfirm ansible
 rm -rf /root/.ansible
 
 # Packer's QEMU builder seems to fail to remove the SSH key

packer/packer-template.json

@@ -9,6 +9,7 @@
     "cmd_cow"     : "<tab><end> cow_spacesize=1G<enter>",
     "cmd_cow_uefi": "e<down><down><down><end> cow_spacesize=1G<F10>",
     "cmd_ssh"     : "<wait60>systemctl start sshd && mkdir -p -m 0700 /root/.ssh<enter>",
+    "cmd_ansible" : "/tmp/ansible_venv/bin/ansible-playbook",
     "memory"      : "2048",
     "disk_size"   : "65536",
     "off_cmd"     : "poweroff"
@@ -105,6 +106,7 @@
     },
     {
       "type" : "ansible-local",
+      "command": "{{ user `cmd_ansible` }}",
       "playbook_dir" : "../ansible",
       "playbook_file" : "../ansible/site.yaml",
       "extra_arguments" : [
@@ -131,6 +133,7 @@
     },
     {
       "type" : "ansible-local",
+      "command": "{{ user `cmd_ansible` }}",
       "playbook_dir" : "../ansible",
       "playbook_file" : "../ansible/site.yaml",
       "extra_arguments" : [

packer/prepare.sh

@@ -1,6 +1,8 @@
 #!/bin/sh
 
-set -e
+set -ex
+
+ANSIBLE_VENV=/tmp/ansible_venv
 
 set_proxy() {
     if [ -n "$http_proxy" ]; then
@@ -16,5 +18,7 @@ unset_proxy() {
 
 set_proxy
 pacman -Syy --noconfirm --needed archlinux-keyring
-pacman -S --noconfirm --needed ansible
+pacman -S --noconfirm --needed python-pip
+python -m venv "$ANSIBLE_VENV"
+"$ANSIBLE_VENV/bin/pip" install 'ansible>=7,<8'
 unset_proxy