refactor: using ```sh instead of shell

wiki/linux/proxmox.md

@@ -20,13 +20,13 @@ For further information see [the disk management article](./disk-management.md)
 SSH into Proxmox.
 Enlarge a disk by using:
 
-```shell
+```sh
 qm resize <vmid> <vm-disk-to-enlarge> <size>
 ```
 
 For example if you want to the disk 100 by 100G (100GibiByte):
 
-```shell
+```sh
 qm resize 100 ide0 +100G
 ```
 
@@ -47,19 +47,19 @@ Finally extend the filesystem `resize2fs /dev/mapper/pve-root`.
 
 On the host system find the usb you're looking to pass through with
 
-```shell
+```sh
 lsusb
 ```
 
 Then assign it to the vm using
 
-```shell
+```sh
 qm set <vm-id> -usb<id-to-set> host=<id-of-the-usb>
 ```
 
 for example
 
-```shell
+```sh
 qm set 101 -usb0 host=aaaa:8816
 ```