* appservice: add and use matrix_homeserver_* vars

* appservice: use the new vars

* Apply suggestions from code review

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

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

This reverts commit 65bfc1396e.

The 1.8.1 image is published now, so we can finally upgrade.

This reverts commit 05ccee9f6f.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1952

No docker tag published yet, [keep an eye on it](https://hub.docker.com/r/halfshot/matrix-hookshot/tags?page=1&ordering=last_updated&name=1.8.1)

Reference: https://ansible-lint.readthedocs.io/en/latest/default_rules/#var-naming

We don't really fix these, but just suppress them,
because they're like that intentionally.

We try to name variables in a way that is consistent with the
configuration key they control. If the upstream component uses
camelCase, we also need to include camelCase in the variable name.

Reference: https://ansible-lint.readthedocs.io/en/latest/default_rules/#no-changed-when

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1939

Details here: https://docs.ansible.com/ansible/devel/porting_guides/porting_guide_6.html#id36

Basically:

```yaml
- name: Prior to 2.13
  debug:
    msg: '[1] + {{ [2] }}'

- name: 2.13 and forward
  debug:
    msg: '{{ [1] + [2] }}'
```

Interestingly, we had been using the new/safe syntax in lofs of places.

We were using the broken one in many others though. Hopefully all
instances were fixed by this patch.

This new version should be buildable on arm64.

See: https://github.com/matrix-org/matrix-hookshot/releases/tag/1.7.0

There's still no prebuild arm64 image, so we continue relying on
self-building there.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1749

https://github.com/matrix-org/matrix-hookshot/releases/tag/1.4.0

The `to_nice_yaml` helper will by default wrap any string YAML values on
the first space after column 80. This can in worst case yield invalid
YAML syntax. More details in Ansible's documentation here:

https://docs.ansible.com/ansible/latest/user_guide/playbooks_filters.html#formatting-data-yaml-and-json

In short, you need to explicitly provide a custom width argument of a
high number of some kind to avoid the line wrapping.

`matrix_nginx_proxy_enabled` is usually set to false by users, this is when
the warning should be displayed.

This fixes parameters not being passed to the provisioning api

Hello, this PR should fix Hookshot container not receiving API calls with the right path because nginx proxy was stripping the /v1 from it.

all features were actually already silently supported 🎉

upstream changelog: https://github.com/matrix-org/matrix-hookshot/releases/tag/1.2.0

to proxy url params in GET requests

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1629

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1505

based on comments in chat:
https://matrix.to/#/!TlZdPIYrhwNvXlBiEk:half-shot.uk/$RbG6itEHVV8J_u5ry1HiFdC76n19M3vmopfQOyRmkKU?via=half-shot.uk&via=matrix.org&via=envs.net

Reverts b1b4ba501fdfaa, 90c9801c560b6, a3c84f78ca9c65a, ..

I haven't really traced it (yet), but on some servers, I'm observing
`ansible-playbook ... --tags=start` completing very slowly, waiting
to stop services. I can't reproduce this on all Matrix servers I manage.
I suspect that either the systemd version is to blame or that some
specific service is not responding well to some `docker kill/rm` command.

`ExecStop` seems to work great in all cases and it's what we've been
using for a very long time, so I'm reverting to that.