common: rebase pacman.conf to pacman 7.0.0.r1.g7cf2b01-1

roles/common/templates/pacman.conf.j2

@@ -38,6 +38,8 @@ Color
 CheckSpace
 VerbosePkgLists
 ParallelDownloads = 5
+DownloadUser = alpm
+#DisableSandbox
 
 # By default, pacman accepts packages signed by keys that its local keyring
 # trusts (see pacman-key and its man page), as well as unsigned packages.