当我尝试使用gitlab-ci安装NVM时，我收到以下错误消息：
.gitlab-ci.yml文件
stages:
- test
Testing:
tags:
- docker
stage: test
image: ubuntu:18.04
before_script:
- apt-get update
- apt-get install curl -y
# Install Node Version Manager (NVM) so we can change the node version
- curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.36.0/install.sh | bash
- nvm --version
错误信息：
$ curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.36.0/install.sh | bash
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 13527 100 13527 0 0 99463 0 --:--:-- --:--:-- --:--:-- 99463
=> Downloading nvm as script to '/root/.nvm'
=> Appending nvm source string to /root/.bashrc
=> Appending bash_completion source string to /root/.bashrc
=> Close and reopen your terminal to start using nvm or run the following to use it now:
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion" # This loads nvm bash_completion
$ nvm --version
/bin/bash: line 116: nvm: command not found
ERROR: Job failed: exit code 1
当我尝试使用exec bash重新加载gitlab-ci中的终端时，gitlab任务会过早地结束，并且不运行脚本的其余部分。
如何在gitlab-ci中安装和使用nvm？