[fix] default callback parameters (#1079)

include/dpp/cluster.h

@@ -1427,7 +1427,7 @@ class DPP_EXPORT cluster {
 	 * @param callback Function to call when the API call completes.
 	 * On success the callback will contain a dpp::confirmation object in confirmation_callback_t::value. On failure, the value is undefined and confirmation_callback_t::is_error() method will return true. You can obtain full error details with confirmation_callback_t::get_error().
 	 */
-	void interaction_followup_create(const std::string &token, const message &m, command_completion_event_t callback);
+	void interaction_followup_create(const std::string &token, const message &m, command_completion_event_t callback = utility::log_error());
 
 	/**
 	 * @brief Edit original followup message to a slash command
@@ -2498,7 +2498,7 @@ class DPP_EXPORT cluster {
 	 * @param callback Function to call when the API call completes.
 	 * On success the callback will contain a dpp::dtemplate object in confirmation_callback_t::value. On failure, the value is undefined and confirmation_callback_t::is_error() method will return true. You can obtain full error details with confirmation_callback_t::get_error().
 	 */
-	void guild_template_create(snowflake guild_id, const std::string &name, const std::string &description, command_completion_event_t callback);
+	void guild_template_create(snowflake guild_id, const std::string &name, const std::string &description, command_completion_event_t callback = utility::log_error());
 
 	/**
 	 * @brief Syncs the template to the guild's current state.