Fix typo in logs
Fix typo in logs

This was introduced in https://github.com/prometheus/mysqld_exporter/commit/73160d968fc9e948aad91b1c56a3c6bb8e14a01f

Signed-off-by: Michael Kopinsky <e0f35dfbbd41d40fde55ae5dc875b22566a0d300@pennmedicine.upenn.edu>

prometheus/mysqld_exporter,prometheus/mysqld_exporter