molecule/kvm/prepare.yml: fix Archlinux preperation

molecule/kvm/prepare.yml

@@ -1,5 +1,5 @@
 ---
-# Copyright (C) 2021-2022 Robert Wimmer
+# Copyright (C) 2021-2023 Robert Wimmer
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 - hosts: opensuse
@@ -26,6 +26,9 @@
       changed_when: false
       failed_when: false
 
+    - name: Updating pacman cache
+      raw: pacman -Sy
+
     - name: Install Python
       ansible.builtin.raw: |
         pacman -S --noconfirm python