Fix build for SQLite
Fix build for SQLite

NOTE: Something has changed recently in SQLite: the lib itself or the
gem. We had broken builds without any change in SQLite code.

  * https://travis-ci.org/hanami/hanami/builds/188262292
  * https://travis-ci.org/hanami/model/jobs/188466061

hanami/model,hlegius/model,lotus/model,hanami/model,cllns/hanami-model