Make port bindings default for those disabling nginx proxy

I changed the conditional statement in prosody systemd template to bind the localhost port by default if people have set ```matrix_nginx_proxy_enabled == false ```.
Hopefully that should make it the default behaviour now.

roles/matrix-jitsi/templates/prosody/matrix-jitsi-prosody.service.j2

@@ -16,8 +16,8 @@ ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }}
 ExecStart={{ matrix_host_command_docker }} run --rm --name matrix-jitsi-prosody \
 			--log-driver=none \
 			--network={{ matrix_docker_network }} \
-			{% if matrix_jitsi_prosody_container_http_host_bind_port %}
-			-p {{ matrix_jitsi_prosody_container_http_host_bind_port }}:{{ matrix_jitsi_prosody_container_http_host_bind_port }}
+			{% if matrix_nginx_proxy_enabled == false %}
+			-p {{ matrix_jitsi_prosody_container_http_host_bind_port }}:5280 \
 			{% endif %}
 			--env-file={{ matrix_jitsi_prosody_base_path }}/env \
 			--mount type=bind,src={{ matrix_jitsi_prosody_config_path }},dst=/config \