Retain fs stats in artifacts zip

[rotu]

The main driver of this is that artifact permissions are lost on upload:

actions/upload-artifact#37
actions/upload-artifact#38

But this will also keep file creation and modification timestamps to assist troubleshooting.

[rmunn]

Looks like the mode parameter is also required in order to preserve Unix file permissions. The zip.append method that actions/toolkit uses is a tiny wrapper around the zip-stream package:

https://github.com/archiverjs/node-archiver/blob/0e0e9ceab65c35e8131701fd2b29ba3c28397385/lib/plugins/zip.js#L55

The entry method in zip-stream looks for the mode property on the incoming data:

https://github.com/archiverjs/node-zip-stream/blob/d2669793807f869da07b38e3e53a088e470702e2/index.js#L157

But nothing in zip-stream handles the stats property.

[rmunn]

I've created #1723, which is essentially this PR plus passing the mode property into zip.append.