CircleCIでGemfileとGemfile.lockがsyncされない

Question

お世話になっております。
下記のpath構成で$ circleci local executeを実行したのですが、/home/circleci/project/Gemfile.lockがないと言われます。
試しに、/home/circleci/project/配下をlsを実行してみたところ、README.mdのみしかsyncされていませんでした。
他に確認するべき箇所はございますでしょうか？

❯ tree -a
.
├── .circleci
│   └── config.yml
├── Gemfile
├── Gemfile.lock
└── README.md

version: 2.1
jobs:
  build:
    docker:
      - image: cimg/ruby:2.7.2
    steps:
      - checkout
      - run:
          command: ls /home/circleci/project/
      - restore_cache:
          name: Cache gem
          keys:
            - v1-bundle-{{ checksum "Gemfile.lock" }}
      - run:
          name: Install gem
          command: bundle config set path 'vender/bundle' || bundle install --deployment
      - save_cache:
          name: Save cache
          key: v1-bundle-{{ checksum "Gemfile.lock" }}
          paths:
            - vender/bundle

実行結果

====>> Checkout code
  #!/bin/bash -eo pipefail
mkdir -p /home/circleci/project && cd /tmp/_circleci_local_build_repo && git ls-files | tar -T - -c | tar -x -C /home/circleci/project && cp -a /tmp/_circleci_local_build_repo/.git /home/circleci/project
====>> ls /home/circleci/project/
  #!/bin/bash -eo pipefail
ls /home/circleci/project/
README.md
====>> Cache gem
Error: 
error computing cache key: template: cacheKey:1:13: executing "cacheKey" at <checksum "Gemfile.lock">: error calling checksum: open /home/circleci/project/Gemfile.lock: no such file or directory

Step failed
====>> Install gem
  #!/bin/bash -eo pipefail
bundle config set path 'vender/bundle' || bundle install --deployment
====>> Save cache
Error: 
Error computing cache key: template: cacheKey:1:13: executing "cacheKey" at <checksum "Gemfile.lock">: error calling checksum: open /home/circleci/project/Gemfile.lock: no such file or directory

Step failed
Success!