Support action issues a warning instead of fail when no file exist in the given path

[capri-xiyue]

TL;DR

Currently, it will fail when no file exist in the given path with error google-github-actions/upload-cloud-storage failed with: ENOENT: no such file or directory. It will be useful that users have the option to choose whether the action should fail or issue a warning when no file exists.

Detailed design

No response

Additional information

No response

[sethvargo]

Hey @capri-xiyue - I think it would be better to skip the step altogether with an if statement:

- steps:
  - uses: 'google-github-actions/upload-cloud-strorage@v1'
    if: '${{ hashFiles(''./path/*'') == '''' }}'

That is strictly more efficient because then GitHub doesn't even download the action source.