Search for a database of boot order shortcuts

Originally created by @sajolida on #8804 (Redmine)

In the current documentation we advertise to configure the BIOS if plugging the USB key is not enough to boot from it. We should instead advertise first the possible keyboard shortcut to choose the boot medium (for example F12 on Thinkpad).

If we could find a database of such keys, we could advertise possible option depending on the brand of the computer.

Parent Task: #8933 (closed)

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