Fix bundle installation error on GitHub Action

Signed-off-by: Yuki Sekiguchi <[email protected]>

Author: aYukiSekiguchi

.github/workflows/linux.yml

@@ -22,5 +22,6 @@ jobs:
         CI: true
       run: |
         gem install bundler rake
+        bundle config set path 'vendor/bundle'
         bundle install --jobs 4 --retry 3
         bundle exec rake test