Not doing {% if matrix_admin %} checks in the YAML also fixes some issues
with indentation being incorrect sometimes.

This should be backward compatible, except for mautrix-signal's case
where `matrix_mautrix_signal_bridge_permissions` previously existed
as a string, not a dictionary. `tasks/validate_config.yml` will catch
the problem an even provide a quick fix.

One that doesn't trip up ansible-lint, causing `load-failure` errors.

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

Based on mautrix-whatsapp, as that's what the bridge software is based on.