Code review comment for ~ines-almeida/launchpad-buildd:update-close-session-for-fetch-service

@Ines I would love to have this merged asap, as both my and Simone's work base on this, and having this pre-requisite MPs juggling around is pretty cumbersome.

The code path for the fetch service cannot be triggered yet, so I do not see any issues with merging this - even without the auth being specced out fully.