Fix issue where only 25 group members were returned

This is because GROUP_CONCAT defaults to 1024. uuid is 40 chars.
1024/40 = ~25

src/database.js

@@ -61,8 +61,9 @@ async function initialize() {
         // note the pool also has an 'acquire' event but that is called whenever we do a getConnection()
         connection.on('error', (error) => debug(`Connection ${connection.threadId} error: ${error.message} ${error.code}`));
 
-        connection.query('USE ' + gDatabase.name);
+        connection.query(`USE ${gDatabase.name}`);
         connection.query('SET SESSION sql_mode = \'strict_all_tables\'');
+        connection.query('SET SESSION group_concat_max_len = 65536'); // GROUP_CONCAT has only 1024 default
     });
 }