I don't understand the documentation of exclude_file:

File with lines that should not be checked for spelling mistakes.

This parameter is optional; by default codespell will check all lines.

uses: codespell-project/actions-codespell@master
with:
  exclude_file: src/foo

Does it exclude lines or files? If it excludes specific lines, please give an example how to achieve that. If it excludes files, remove any reference to line and explain how skip and exclude_file are different.