workflows: update workflows, templates to support arm64. (#14653)

* set 'var_arm64' to no in all ct scripts

* update files in .github to support arm64

ct/pulse.sh

@@ -12,6 +12,7 @@ var_ram="${var_ram:-1024}"
 var_disk="${var_disk:-4}"
 var_os="${var_os:-debian}"
 var_version="${var_version:-13}"
+var_arm64="${var_arm64:-no}"
 var_unprivileged="${var_unprivileged:-1}"
 
 header_info "$APP"