Upgrade server hardware (2017-2019 edition)

Originally created by @Dr_Whax on #11680 (Redmine)

This includes:

• storage: update the spreadsheet we did for #10851 (closed) and draw conclusions wrt. how much more storage we need to add
• reproducible builds’ needs
• running the test suite on bare metal?
• asking server hardware sponsorship or discount to hardware vendors?
• using the cloud?

Blueprint: https://tails.boum.org/blueprint/hardware_for_automated_tests_take3/

Subtasks

• #11806 (closed)
• #13425 (closed)
• #15501 (closed)
• #15780 (closed)

Related issues

• Related to #10851 (closed)
• Related to tails#14601 (closed)
• Related to #16960 (closed)