Remount /mnt/extra-disk on reboot

net/gce.sh

@@ -667,6 +667,10 @@ if [[ -f /solana-scratch/.instance-startup-complete ]]; then
     if "$enableGpu"; then
       cat enable-nvidia-persistence-mode.sh
     fi
+
+    if [[ -n $validatorAdditionalDiskSizeInGb ]]; then
+      cat mount-additional-disk.sh
+    fi
   )
 
   # Skip most setup on instance reboot

net/scripts/mount-additional-disk.sh

@@ -6,8 +6,9 @@ disk=sdb
 if ! lsblk | grep -q ${disk} ; then
   echo "${disk} does not exist"
 else
+  sudo mount /dev/"$disk" "$mount_point"
   if mount | grep -q ${disk} ; then
-    echo "${disk} is already mounted"
+    echo "${disk} is mounted"
   else
     sudo mkfs.ext4 -F /dev/"$disk"
     sudo mkdir -p "$mount_point"