Expand Debian VM disk partition

[kan84]

Through proxmox ui, I expanded the disk space from 32 GB to 40 GB.

lsblk:
```
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
nvme0n1 259:0 0 465.8G 0 disk
├─nvme0n1p1 259:1 0 1007K 0 part
├─nvme0n1p2 259:2 0 1G 0 part /boot/efi
└─nvme0n1p3 259:3 0 464.8G 0 part
├─pve-swap 253:0 0 8G 0 lvm [SWAP]
├─pve-root 253:1 0 96G 0 lvm /
├─pve-data_tmeta 253:2 0 3.4G 0 lvm
│ └─pve-data-tpool 253:4 0 337.9G 0 lvm
│ ├─pve-data 253:5 0 337.9G 1 lvm
│ ├─pve-vm--100--disk--0 253:6 0 40G 0 lvm
│ ├─pve-vm--101--disk--0 253:7 0 32G 0 lvm
│ ├─pve-vm--102--disk--0 253:8 0 4M 0 lvm
│ ├─pve-vm--102--disk--1 253:9 0 200G 0 lvm
│ └─pve-vm--102--disk--2 253:10 0 4M 0 lvm
└─pve-data_tdata 253:3 0 337.9G 0 lvm
└─pve-data-tpool 253:4 0 337.9G 0 lvm
├─pve-data 253:5 0 337.9G 1 lvm
├─pve-vm--100--disk--0 253:6 0 40G 0 lvm
├─pve-vm--101--disk--0 253:7 0 32G 0 lvm
├─pve-vm--102--disk--0 253:8 0 4M 0 lvm
├─pve-vm--102--disk--1 253:9 0 200G 0 lvm
└─pve-vm--102--disk--2 253:10 0 4M 0 lvm
```
lvs:
```
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
data pve twi-aotz-- <337.86g 57.79 2.10
root pve -wi-ao---- 96.00g
swap pve -wi-ao---- 8.00g
vm-100-disk-0 pve Vwi-aotz-- 40.00g data 78.70
vm-101-disk-0 pve Vwi-aotz-- 32.00g data 96.87
vm-102-disk-0 pve Vwi-a-tz-- 4.00m data 14.06
vm-102-disk-1 pve Vwi-a-tz-- 200.00g data 66.39
vm-102-disk-2 pve Vwi-a-tz-- 4.00m data 1.56
```
vgs:
```
VG #PV #LV #SN Attr VSize VFree
pve 1 8 0 wz--n- <464.76g 16.00g
```

I can see that disk space has been provisioned - pve-vm--100--disk--0 253:6 0 40G 0 lvm
But when I check inside the vm I do not see any unallocated space.

sudo fdisk -l /dev/sda
```
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 65107967 65105920 31G 83 Linux
/dev/sda2 65110014 67106815 1996802 975M 5 Extended
/dev/sda5 65110016 67106815 1996800 975M 82 Linux swap / Solaris
```
I was planning to use gparted to expand the main partition but I was wondering if I should see an unallocated partition using fdisk.