Fix occasional race conditions when testing

[jaywardell]

When testing in Xcode, I was encountering an occasional crash that was happening when other tests were being run (tests other than mine).

They appear to be related to these tests not calling PublishingContext.initialize() before calling render(), though actually there are a few other tests that don't call PublishingContext.initialize() before calling render() and don't seem to cause this issue.

This behavior can be reproduced pretty reliably by control-clicking the test button on line 14 of IncludeTests in Include.swift and choosing "Run 'Include Tests' Repeatedly…"

As I say, there are a few tests that can cause this crash, and it's flakey exactly when it will happen.

Still, by calling try PublishingContext.initialize(for: TestSite(), from: #filePath) on init, this crash can be avoided. This is at least the approach that others have used in tests like SubsiteLinkTests in Link.swift.

So I added this to a few tests that seem to cause this crash for me. If others encounter this with other tests, they can feel free to copy this approach.

[twostraws]

Thank you! We've used this init() solution elsewhere, and it's really flaky – so easy to forget, and so damaging. While we think up a better solution we'll need to proceed with this. Did it pass SwiftLint okay?

[JPToroDev]

I've got a fix to this janky init() hack we've been using. Will push shortly.

[jaywardell]

I had forgotten to run SwiftLint on this PR. Sorry.

It looks like this is probably moot given #420. It should go without saying, but feel free to give that PR priority and close this one if it's not needed.

[JPToroDev]

I'm going to close this PR since #420 introduces a long-term solution. Excited to get your other PRs across the finish line!

[jaywardell]

👍