Update Icedove design documentation wrt. the autoconfig wizard
https://tails.boum.org/contribute/design/#index41h3 should be updated at the same time as we enble the auto configuration wizard in Tails.
Feature Branch: 451f:tails/feature/11215+icedove_design_doc
Parent Task: #6154 (closed)
To upload designs, you'll need to enable LFS and have admin enable hashed storage. More information