How do I use the CLI to upload support case attachments?

Issue

• Uploading SOSreports, MustGathers, crash dumps, log files, and other files via the Red Hat Customer Portal GUI is tedious and time consuming because system administrators must copy this information from the affected system(s) to a desktop and then upload from the desktop.
• Sometimes customer firewall rules prohibit desktop uploads.
• System administrators need a convenient way to do these uploads directly from affected systems via CLI.