Comment # 2 on bug 1208939 from Stefan Dirsch

I guess this is the change in our kernel for 6.2.1 to no longer load unsigned
kernel modules. :-( 

In order to verify this either boot an older kernel or disable Secureboot in
your Firmware/BIOS.

But I see you're trying to use the openGPU driver from nvidia now. AFAIK GT1030
is still Pascal architecture, which is not supported by this driver. You would
need to select nvidia-driver-G06-kmp-default instead and remove again
nvidia-open-driver-G06-signed-kmp-default and kernel-firmware-nvidia-gsp-G06.