message: Rename prepare function to checkout
diff: # Functions are any command that can be run.
  functions:
  - prepare:
  + checkout:
  - command: git.get_project
  params:
  directory: src
  @@ -72,12 +72,12 @@ functions:
  # Tasks will show up as the individual blocks in the Evergreen UI that can
  # pass or fail.
  tasks:
  - - name: prepare
  + - name: checkout
  depends_on: []
  commands:
  - - func: prepare
  + - func: checkout
  - name: install_nvm
  - depends_on: [prepare]
  + depends_on: [checkout]
  commands:
  - func: install_nvm
  - name: install_node
  