At some point in recent releases, "%" no longer matches localhost
in new setups, so specify both.

mariadb server emits warnings otherwise:

Using unique option prefix 'key_buffer' is error-prone and can break in
the future. Please use the full name 'key_buffer_size' instead.

Using unique option prefix 'sort_buffer' is error-prone and can break in
the future. Please use the full name 'sort_buffer_size' instead.

mysqldump chokes when dumping big tables. Also 16M will be the default
when running on Buster's mariadb 10.3.

The addition of 'in-container' in float@dee0b41c makes it
redundant to ship our own custom wrapper just for noblogs.

Fixes ai/noblogs-wp#38.

These are a copy of our current configuration.

It now works at least for the homepage.