Merge branch 'zj-clean-gems' into 'master'

Clean cache after bundling

See merge request !10047

.gitlab-ci.yml

@@ -19,7 +19,7 @@ before_script:
   - source ./scripts/prepare_build.sh
   - cp config/gitlab.yml.example config/gitlab.yml
   - bundle --version
-  - '[ "$USE_BUNDLE_INSTALL" != "true" ] || retry bundle install --without postgres production --jobs $(nproc) $FLAGS'
+  - '[ "$USE_BUNDLE_INSTALL" != "true" ] || retry bundle install --without postgres production --jobs $(nproc) --clean $FLAGS'
   - retry gem install knapsack
   - '[ "$SETUP_DB" != "true" ] || bundle exec rake db:drop db:create db:schema:load db:migrate add_limits_mysql'