addRole method
Add a role to a member in the guild.
Implementation
Future<void> addRole(Snowflake id, Snowflake roleId, {String? auditLogReason}) async {
final route = HttpRoute()
..guilds(id: guildId.toString())
..members(id: id.toString())
..roles(id: roleId.toString());
final request = BasicRequest(route, method: 'PUT', auditLogReason: auditLogReason);
await client.httpHandler.executeSafe(request);
}