gotosocial: update to version 0.8.1

Changelog (taken from https://github.com/superseriousbusiness/gotosocial/releases/tag/v0.8.1):

v0.8.1 Even More Scurrilous Sloth

Hello! Cheeky small bugfix release. 0.8.0 accidentally broke bookmarks on Postgres and this fixes that, thanks @handlerug !
Migration Notes
Upgrade from 0.8.0

Easy upgrade, no datab

ase migrations.

There are two small typo fixes in the example config.yaml file, so you may need to make these changes in your config.yaml too. See here: fd3bf92
Binary/tar

    Stop GoToSocial
    Untar the new release, including the web assets and html templates.
    Edit your config.yaml file as necessary (see below).
    Start GoToSocial

Docker

    Stop GoToSocial.
    Pull the new docker container (superseriousbusiness/gotosocial:0.8.1 or superseriousbusiness/gotosocial:latest)
    Start GoToSocial.

Upgrade from prior to 0.8.0

Follow instructions for updating to 0.8.0 (https://github.com/superseriousbusiness/gotosocial/releases/v0.8.0), but replace version numbers with 0.8.1 instead.
Detailed Changelog

    4dbf9a2 [bugfix] fix small config typos (#1707)
    0744477 [bugfix] Fix the bookmarks list API endpoint returning an empty array (#1700)

(nikita)