MDEV-19123 Change default charset from latin1 to utf8mb4

Changing the default server character set from latin1 to utf8mb4.

mysql-test/suite/encryption/r/tempfiles.result

@@ -17,6 +17,7 @@ from seq_0_to_9 as s1, seq_0_to_26 as s2;
 update t1 set c=v, t=v;
 select sql_big_result t,count(t) from t1 group by t limit 10;
 t	count(t)
+{	10
 a	10
 b	10
 c	10
@@ -26,7 +27,6 @@ f	10
 g	10
 h	10
 i	10
-j	10
 drop table t1;
 reset master;
 set @save_binlog_cache_size=@@global.binlog_cache_size;