Design a 2nd ISO testing machine

Originally created by @intrigeri on #11011 (Redmine)

We need to update a bit our hardware specs/research work given the recent developments and plans.

Blueprint: https://tails.boum.org/blueprint/hardware_for_automated_tests_take2/

Parent Task: tails/sysadmin#11009

Related issues

• Related to tails/tails#6729
• Blocked by tails/sysadmin#11113