Packer bootstrap tweaks

Much speed by using our Geo mirror + maximum freshness by not hard coding the bootstrap version anymore + extreme future-proofness by creating the temporary server with Ubuntu 22.04. ️

roles/install_arch/tasks/main.yml

@@ -44,7 +44,7 @@
 
 - name: download bootstrap image
   get_url:
-    url: https://mirrors.kernel.org/archlinux/iso/{{ bootstrap_version }}/archlinux-bootstrap-{{ bootstrap_version }}-x86_64.tar.gz
+    url: https://geo.mirror.pkgbuild.com/iso/{{ bootstrap_version }}/archlinux-bootstrap-{{ bootstrap_version }}-x86_64.tar.gz
     dest: /tmp/
 
 - name: extract boostrap image  # noqa 208