Update openwrt.sh

add pve 8
fixes https://github.com/tteck/Proxmox/issues/1528

vm/openwrt.sh

@@ -157,7 +157,7 @@ function msg_error() {
 }
 
 function pve_check() {
-  if [ $(pveversion | grep -c "pve-manager/7\.[2-9]") -eq 0 ]; then
+  if ! pveversion | grep -Eq "pve-manager/(7\.[2-9]|8\.[0-9])"; then
     echo -e "${CROSS} This version of Proxmox Virtual Environment is not supported"
     echo -e "Requires PVE Version 7.2 or higher"
     echo -e "Exiting..."