[test] create Gemfile.lock in build directory
[test] create Gemfile.lock in build directory

refs #1302

Reported by Kazuhiko Shiozaki. Thanks!!!

kenhys/groonga,komainu8/groonga,groonga/groonga,cosmo0920/groonga,cosmo0920/groonga,cosmo0920/groonga,hiroyuki-sato/groonga,naoa/groonga,kenhys/groonga,hiroyuki-sato/groonga,komainu8/groonga,myokoym/groonga,komainu8/groonga,hiroyuki-sato/groonga,cosmo0920/groonga,redfigure/groonga,myokoym/groonga,kenhys/groonga,groonga/groonga,naoa/groonga,redfigure/groonga,kenhys/groonga,groonga/groonga,komainu8/groonga,naoa/groonga,redfigure/groonga,komainu8/groonga,myokoym/groonga,komainu8/groonga,redfigure/groonga,cosmo0920/groonga,kenhys/groonga,myokoym/groonga,redfigure/groonga,hiroyuki-sato/groonga,naoa/groonga,cosmo0920/groonga,cosmo0920/groonga,hiroyuki-sato/groonga,hiroyuki-sato/groonga,naoa/groonga,komainu8/groonga,groonga/groonga,redfigure/groonga,kenhys/groonga,kenhys/groonga,myokoym/groonga,groonga/groonga,groonga/groonga,myokoym/groonga,cosmo0920/groonga,kenhys/groonga,redfigure/groonga,myokoym/groonga,myokoym/groonga,hiroyuki-sato/groonga,komainu8/groonga,naoa/groonga,naoa/groonga,hiroyuki-sato/groonga,groonga/groonga,redfigure/groonga,groonga/groonga,naoa/groonga