make the listen address configurable - fixes #927

sadly `fastify.listen` doesn't support passing more than 1 address

packages/backend/src/server/ServerService.ts

@@ -262,7 +262,7 @@ export class ServerService implements OnApplicationShutdown {
 				}
 			});
 		} else {
-			fastify.listen({ port: this.config.port, host: '0.0.0.0' });
+			fastify.listen({ port: this.config.port, host: this.config.address });
 		}
 
 		await fastify.ready();