local-lvm（LVM-Thin）の削除

root@pve:~# lvremove pve/data && lvextend -l +100%FREE pve/root && resize2fs /dev/pve/root

Do you really want to remove and DISCARD active logical volume pve/data? [y/n]: y
  Logical volume "data" successfully removed
  Size of logical volume pve/root changed from 7.75 GiB (1984 extents) to 27.62 GiB (7071 extents).
  Logical volume pve/root successfully resized.
resize2fs 1.44.5 (15-Dec-2018)
Filesystem at /dev/pve/root is mounted on /; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 4
The filesystem on /dev/pve/root is now 7240704 (4k) blocks long.

root@pve:~# df -h
Filesystem            Size  Used Avail Use% Mounted on
udev                  3.9G     0  3.9G   0% /dev
tmpfs                 797M  8.7M  788M   2% /run
/dev/mapper/pve-root   28G  2.3G   24G   9% /
tmpfs                 3.9G   40M  3.9G   1% /dev/shm
tmpfs                 5.0M     0  5.0M   0% /run/lock
tmpfs                 3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/fuse              30M   16K   30M   1% /etc/pve
tmpfs                 797M     0  797M   0% /run/user/0