The forkMode parameter has been deprecated in Surefire 2.14, and with the upcoming 3.0 release, it's finally time to remove the parameter once and for all.

Reviewer instructions

Removing the forkMode ended up being a quite comprehensive change. Throughout the refactoring/restructuring process, I ran the tests and integration tests often, to ensure equivalent behavior. I re-purposed most forkMode tests to test the forkCount parameter, removing a few that were per definition redundant.

Each commit should address a "sub-issue" I had to tackle to remove the forkMode. If the entire diff looks daunting, I can recommend reviewing commit-by-commit. Each commit should be a version that compiles on its own.

Here are a few more pointers for reviewing:

• Read this article about migrating forkMode to forkCount.
• Start with the first commit, where I remove the most important traces of the forkMode parameter, before moving on to the entire diff.
• I removed the migration guide from the docs. Is that okay or would we like to keep it up for now?
• I left some convenience methods for the different fork modes in the SurefireLauncher, let me know if you'd like me to unfold that.
• I avoided the term "fork mode" as much as possible, but still left some traces where it made sense.

What's next?

While working on this, I noticed a few codebase styling issues that I'd like to refactor. To keep the diff of this PR sensible, I decided it would be better to open a separate PR for that. So you can expect another PR incoming 😉

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