Add recruitment FAQ to handbook

[yongrenjie]

Summary

Proposal to add the recruitment FAQ to the handbook.

@joseph-palmer @IFenton @KatrionaGoldmann and I are all in favour of it (I think).

The FAQ is public anyway so there is no change in terms of who can access the information.

Impact

1. Make the rest of the handbook (which contains some really good info) more visible to potential applicants who click on the FAQ link
2. Enable anyone in the team to contribute and review changes
3. Consolidation of information (which we have broadly been trying to move towards in the past year or so)
4. Avoids potential issues arising from having to pass control of the hut23 recruitment HackMD account from one person to another (due to people e.g. leaving the Turing or being on leave)

Sections

• "Applicants Look Here Now!"

Updates

Created draft PR: #139