services.mysql: on create initial databases add savety statement 'IF NOT EXISTS' for edgecases

                # Create initial databases

                if ! test -e "${cfg.dataDir}/${database.name}"; then

                    echo "Creating initial database: ${database.name}"

                    ( echo 'create database `${database.name}`;'

                    ( echo 'CREATE DATABASE IF NOT EXISTS `${database.name}`;'

                      ${lib.optionalString (database.schema != null) ''

                        echo 'use `${database.name}`;'