The when statement is supposed to be on the block, not on the individual task.

It affects all tasks within the block (they're all to be executed when ma1sd is enabled and self-building is requested0.

The tag format used in the `ma1sd` repo have change. Versions no longer
start with 'v', and when building for non-amd64, we also need to strip
off the '-$arch' bit from the Docker image name.

Further, when building the .jar file, `ma1sd` currently names the .jar
based on the project's directory, which we call 'docker-src'. This means
other parts of the `ma1sd` build can't find the .jar file. Remedy this
by ensuring that the dir is called `docker-src/ma1sd`.

- https://github.com/icewind1991/mx-puppet-steam is the link that's referenced by the documentation.
- The previous link, https://github.com/matrix-steam/mx-puppet-steam, is invalid/inaccessible to the public.

Related to #554 (Github Pull Request).

https://github.com/matrix-discord/mx-puppet-discord/issues/80

Thanks Sorunome for setting up the automated build

4.5.1.3 fixes a security vulnerability:
https://github.com/coturn/coturn/security/advisories/GHSA-c8r8-8vp5-6gcm

Signed-off-by: Tulir Asokan <tulir@maunium.net>

`matrix_container_images_self_build` was not really doing anything
anymore. It previously was influencing `matrix_*_self_build` variables,
but it's no longer the case since some time ago.

Individual `matrix_*_self_build` variables are still available.
People that would like to toggle self-building for a specific component
ought to use those.

These variables are also controlled automatically (via
`group_vars/matrix_servers`) depending on `matrix_architecture`.

In other words, self-building is being done automatically for
all components when they don't have a prebuilt image for the specified
architecture. Some components only support `amd64`, while others also
have images for other architectures.

ma1sd 2.4.0 announced experimental support for arm64.
We're making use of those arm64 images instead of self-building.

Related to https://github.com/vector-im/riot-web/pull/13914

Certain people organize their inventory in a different way
and we'd like to accommodate them.

Related to #542 (Github Issue).

Fixes #542 (Github Issues).

Fixes #539 (Github Issue).

Fixes #523 (Github Issue).

Besides /_synapse/admin, there are other things like
/_synapse/oidc, etc.

We should just proxy everything.

Fixes #534 (Github Issue).