Fix broken links for mysql

mysql/content.md

@@ -92,7 +92,7 @@ This variable is mandatory and specifies the password that will be set for the M
 
 ### `MYSQL_DATABASE`
 
-This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](http://dev.mysql.com/doc/en/adding-users.html)) to this database.
+This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](https://dev.mysql.com/doc/refman/en/creating-accounts.html)) to this database.
 
 ### `MYSQL_USER`, `MYSQL_PASSWORD`
 

percona/content.md

@@ -96,7 +96,7 @@ By default, `root` can connect from anywhere. This option restricts root connect
 
 ### `MYSQL_DATABASE`
 
-This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](http://dev.mysql.com/doc/en/adding-users.html)) to this database.
+This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](https://dev.mysql.com/doc/refman/en/creating-accounts.html)) to this database.
 
 ### `MYSQL_USER`, `MYSQL_PASSWORD`