Allow for multiple & wildcard files on `:file:` arg for cypress reports

[mjsir911]

Hello,

We have the need to include javascript cypress coverage reports in our sphinx documentation. Unfortunately, cypress outputs multiple junit xml report files, one per test-file.

This is really awkward to get working with sphinx-test-reports. Would it make sense to modify the directive's :file: argument to accept 1+ files & bundle them together?

Thanks,