ElasticBeanstalkでのデプロイで'You need to install git to be able to use gems from git repositories.'

$ eb deploy
WARNING: Deploying a previously deployed commit.
INFO: Environment update is starting.                               
INFO: Deploying new version to instance(s).                         
ERROR: [Instance: xxxxxx] Command failed on instance. Return code: 11 Output: (TRUNCATED)...rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
You need to install git to be able to use gems from git repositories. For help
installing git, please refer to GitHub's tutorial at
https://help.github.com/articles/set-up-git. 
Hook /opt/elasticbeanstalk/hooks/appdeploy/pre/10_bundle_install.sh failed. For more detail, check /var/log/eb-activity.log using console or EB CLI.
INFO: Command execution completed on all instances. Summary: [Successful: 0, Failed: 1].
INFO: New application version was deployed to running EC2 instances.
ERROR: Update environment operation is complete, but with errors. For more information, see troubleshooting documentation.

こんなのが出てしまい、調べてみると下記がヒット。

そして以下も参考にしつつgitの設定を書く。

.ebextensions/01-git.config

packages:
  yum:
    git: []

eb logsには世話になる。