Test the stats:fetch command, and report if Packagist download count fails

[gcavanunez]

Highlights

• Tests stats:fetch command
• Mocks HTTP and GitHub requests
• Reports if 500 on Packagist

Notes

• We try to fetch on all packages, regardless if they exist or not in packagist.org, which feel odd
• If packagist.org, for whatever reason, fails to report, we would no longer overwrite download counts

reference

• Add tests #89
• Throw exception or send notice or something if Packagist download count lookup fails #88

[mattstauffer]

Great work! Just a few notes.

[mattstauffer]

If I'm understanding this test correctly, it means a failed request doesn't overwrite our local stats, right? If so, I'd change the method name to indicate this:

Suggested change

	public function fetch_stats_does_not_overwrite_packagist_stats(): void
	public function failed_stats_fetch_does_not_overwrite_packagist_stats(): void

[mattstauffer]

Maybe in another PR, but this feels silly to have to create the maintainer in this test when it isn't relevant to this test. Could we add a factory state (I think that's what they're called these days) for the project factory so we could just chain withMaintainer() when creating the project?

[mattstauffer]

Great work @gcavanunez!