CUDA 10.1 is not being installed on Ubuntu 19.04

gcc (Ubuntu 8.3.0-6ubuntu1) 8.3.0
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nvidia-smi

±----------------------------------------------------------------------------+
| NVIDIA-SMI 418.56 Driver Version: 418.56 CUDA Version: 10.1 |
|-------------------------------±---------------------±---------------------+
| GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 GeForce RTX 208… Off | 00000000:01:00.0 On | N/A |
| 35% 25C P8 3W / 260W | 367MiB / 10986MiB | 2% Default |
±------------------------------±---------------------±---------------------+

±----------------------------------------------------------------------------+
| Processes: GPU Memory |
| GPU PID Type Process name Usage |
|=============================================================================|
| 0 1288 G /usr/lib/xorg/Xorg 24MiB |
| 0 1328 G /usr/bin/gnome-shell 58MiB |
| 0 1674 G /usr/lib/xorg/Xorg 115MiB |
| 0 1825 G /usr/bin/gnome-shell 167MiB |
±----------------------------------------------------------------------------+

cuda-installer.log shows:

[INFO]: Uncompressing NVIDIA Accelerated Graphics Driver for Linux-x86_64 418.67…

[INFO]:

[INFO]: ERROR: An NVIDIA kernel module ‘nvidia-drm’ appears to already be loaded in your kernel. This may be because it is in use (for example, by an X server, a CUDA program, or the NVIDIA Persistence Daemon), but this may also happen if your kernel was configured without support for module unloading. Please be sure to exit any programs that may be using the GPU(s) before attempting to u
[INFO]: pgrade your driver. If no GPU-based programs are running, you know that your kernel supports module unloading, and you still receive this message, then an error may have occured that has corrupted an NVIDIA kernel module’s usage count, for which the simplest remedy is to reboot your computer.

nvidia-installer.log shows:

ERROR: An NVIDIA kernel module ‘nvidia-drm’ appears to already be loaded in your kernel. This may be because it is in use (for example, by an X server, a CUDA program, or the NVIDIA Persistence Daemon), but this may also happen if your kernel was configured without support for module unloading. Please be sure to exit any programs that may be using the GPU(s) before attempting to upgrade your driver. If no GPU-based programs are running, you know that your kernel supports module unloading, and you still receive this message, then an error may have occured that has corrupted an NVIDIA kernel module’s usage count, for which the simplest remedy is to reboot your computer.
ERROR: Installation has failed. Please see the file ‘/var/log/nvidia-installer.log’ for details. You may find suggestions on fixing installation problems in the README available on the Linux driver download page at www.nvidia.com.

Ubuntu 19.04 is not a supported environment for CUDA 10.1 development:

https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html

If you simply want to get the driver loaded, please read the information output that you posted in your question.