Update Windows secureboot certificates on Proxmox

1. Check with the following command, if the new certificates are already installed

[System.Text.Encoding]::ASCII.GetString((Get-SecureBootUEFI db).bytes) -match 'Windows UEFI CA 2023'

2. If the return value is false, go in the registry to Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot and set the value (as hex) to 0x00005944
3. Now enroll the new certificates over the Proxmox GUI (Click on the EFI Disk, Disk Action and Enroll Updated Certificates)
4. Shutdown the VM and Boot it (not a reboot!)
5. Open the registry and got to Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot, wait until a new key exists which starts like RestartRequiredFor.... And in Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot\Servicing the UEFICA2023Statusshould be InProgress
6. Then reboot and wait until AvaiableUpdates the value is 0x00004000 (Registry, under Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot). In the Registry under Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecureBoot\Servicing, the UEFICA2023Status should be Updated
7. Now reexecute the command from step one, it should now return True