Bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Update jitsi v8615 -> v8922

Update synapse 1.91.0 -> 1.91.1

Update honoroit 0.9.18 -> 0.9.19

Update grafana 10.1.0 -> 10.1.1

Update sliding-sync 0.99.7 -> 0.99.8

Related to #2851 

Fixes #2861

Improved README descriptions

Update borg v1.2.4 -> v1.2.5

Added SchildiChat DNS record

make synapse even more quiet

fix schildichat link in readme

Related to: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/2851

add SchildiChat client

Update synapse 1.90.0 -> 1.91.0

Hopefully fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/2849

Related to:
- https://github.com/matrix-org/synapse/issues/16101
- https://github.com/matrix-org/synapse/issues/16208

Add a small tip to maintenance-migrating.md

matrix-synapse/tasks/setup_uninstall.yml would previously not run unless
Synapse was completely disabled.

`spam_checker` has been deprecated for quite a while.
While it still probably works and while newer versions of
mjolnir-antispam still use it, we should switch to the new API.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/2846

Upgrade sliding-sync (v0.99.5 -> v0.99.7)

* Update docs for older appservice bridges to enable legacy authorization

* Update docs/configuring-playbook-bridge-appservice-discord.md

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

* Update docs/configuring-playbook-bridge-appservice-webhooks.md

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

* further fix formatting

---------

Co-authored-by: blotree <teruyo@touhou-project.com>
Co-authored-by: Slavi Pantaleev <slavi@devture.com>

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/2842

`devture_traefik_provider_configuration_extension_yaml` should not be
set automatically by the playbook. It's a variable to be used by users.

Moreover, setting for for everyone (not just people who have additional JVBs)
means that for most people the following error will be produced:

> 'dict object' has no attribute 'jitsi_jvb_servers'

.. as detailed in https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/2844

Fixes a regression introduced in: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/2842

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/2842