fix(system-upgrade): Fix ever expanding fstab line

This patch fixes a bug, where the longhorn fstab entry grows
indefinitely every time the lvm setup script is run. This is due to a
bug in the sed script that replaces only the first part of the fstab
entry instead of the entire line.

infrastructure/system-upgrades/longhorn-lvm.yaml

@@ -60,7 +60,7 @@ stringData:
     if ! grep '/var/lib/longhorn' /etc/fstab; then
       echo "/dev/mapper/${VG_NAME}-${LV_NAME}    /var/lib/longhorn           xfs     defaults,x-systemd.device-timeout=0 0 0" >> /etc/fstab
     else
-      sed -i "s%/dev/mapper/${VG_NAME}-${LV_NAME}*%/dev/mapper/${VG_NAME}-${LV_NAME}    /var/lib/longhorn           xfs     defaults,x-systemd.device-timeout=0 0 0%" /etc/fstab
+      sed -i "s%^/dev/mapper/${VG_NAME}-${LV_NAME}.*%/dev/mapper/${VG_NAME}-${LV_NAME}    /var/lib/longhorn           xfs     defaults,x-systemd.device-timeout=0 0 0%" /etc/fstab
     fi
     systemctl daemon-reload
 ---