fix(iso): Do an initial pacman database update (#1)

setup.sh

@@ -17,6 +17,10 @@ function we_are_changerooted () {
     fi
 }
 
+function update_pacman_db () {
+    pacman -Sy
+}
+
 function install_pkgs () {
     printf -- '%s\n' 'Installing packages ...'
     pacman -S --needed --noconfirm "${@}"
@@ -471,6 +475,7 @@ function main () {
         install_os_in_chroot
     else
         set_ntp
+        update_pacman_db
         install_pkgs 'jq'
         declare zfs_part
         zfs_part="$(get_parts 'zfs')"