Ensure that we don't use bin logs by default

MySQL 8 comes with bin logs enabled, and that can end using
big space on volumes for near nothing. So ensure that both
MySQL and MariaDB, by default, disable them.

Note this can be changed whenever/if we want to test primary +
replica configurations, but that's another story. For standalone
runs better have bin logs disabled.

Author: stronk7

db.mariadb.yml

@@ -11,6 +11,7 @@ services:
               --collation-server=utf8mb4_bin
               --innodb_file_per_table=On
               --wait-timeout=28800
+              --skip-log-bin
     environment:
       MYSQL_ROOT_PASSWORD: "m@0dl3ing"
       MYSQL_USER: moodle

db.mysql.yml

@@ -9,6 +9,7 @@ services:
     command: >
                 --character-set-server=utf8mb4
                 --collation-server=utf8mb4_bin
+                --skip-log-bin
     environment:
       MYSQL_ROOT_PASSWORD: "m@0dl3ing"
       MYSQL_USER: moodle