我正在尝试为以下Github操作创建缓存：

name: dockercompose
on: push

jobs:
  test:
    runs-on: ubuntu-18.04
    steps:
      - uses: actions/checkout@v1

      - name: Cache Docker Compose
        id: cache-docker
        uses: actions/cache@v1
        with:
          path: fhe_app/
          key: cache-docker

      - name: Build the stack
        run: docker-compose up -d
        working-directory: fhe_app/

发以下Dockerfile：

FROM tensorflow/tensorflow:nightly-py3

# set work directory
WORKDIR /usr/src/app

# set environment variables
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1

# install dependencies
RUN python3 -m pip install --upgrade pip
COPY local_requirements.txt /usr/src/app/local_requirements.txt

RUN \
apt-get update && \
apt-get -y install python3 postgresql-server-dev-10 gcc python3-dev musl-dev netcat

RUN python3 -m pip install -r local_requirements.txt

# copy entrypoint.sh
COPY entrypoint.sh /usr/src/app/entrypoint.sh
RUN chmod +x entrypoint.sh

# copy project
COPY . /usr/src/app/

# run entrypoint.sh
ENTRYPOINT ["/usr/src/app/entrypoint.sh"]

当推送到Github时，我收到的不是成功消息，而是：

Cache Docker Compose
Cache not found for input keys: cache-docker.

并且：

Post Cache Docker Compose
Post job cleanup.
/bin/tar -cz -f /home/runner/work/_temp/e13e2694-e020-476d-888e-cb29cb9184b6/cache.tgz -C /home/runner/work/fhe_server/fhe_server/fhe_app .
/bin/tar: ./app: file changed as we read it
##[warning]The process '/bin/tar' failed with exit code 1

我还有其他不使用Docker的yml文件可以正确缓存，因此yml的整体结构应该很好。这是缓存docker-compose的正确方法吗？