Make the build pass on Drupal 8.8

Yay, thanks!

Actually, it seems tests now fail on 8.8.x because of this. :/

@see https://www.drupal.org/pift-ci-job/1465611

I don't fully understand why we're doing this here, but it seems to break things. I suspect because of #3084983: Move all the code related to path aliases to a new (required) "path_alias" module

But hrmph, reverting this commit locally doesn't get tests to pass on 8.8.x. No time to dig deeper right now, but re-opening cuz our tests are failing on 8.8.x.

This seems to work locally on both 8.7.x and 8.8.x. Yay for adding more technical debt to contrib so core can remove its own! 🤦‍♂️

This is a safer way to handle version_compare() for the current state of things. :/

@see #3093130: Between alpha1 and X.Y.0 official \Drupal::VERSION should not be "8.8.0-dev" since it doesn't work for Semver::satisfies() for more.

Since that's green on all branches, I committed #9 and pushed to 8.x-1.x.

Back to fixed.

Phew,
-Derek

Well, yay! In response to my evil, ugly-workaround, we already fixed 8.8.x about this. ;)

#3093257: Install path_alias by default in kernel tests to minimize the impact on contrib tests supporting 8.7.x

So maybe we can rip this back out, after all. However, there was talk of adding a deprecation warning about it. :( I'm trying to keep that from happening in 8.8.x, and only in 8.9.x.

Meanwhile, let's confirm the bot is happy now without #9.

Hah, 8.8.x is now failing b/c of #3093294: Specify the $defaultTheme property in all functional tests

#3093294: Specify the $defaultTheme property in all functional tests is now in 8.x-1.x, so 8.8.x tests should pass again. Let's see.

Based on Slack feedback from catch and alexpott, we all agree that #3093333: Consider a deprecation notice if path_alias is needed for tests but not installed explicitly is only going to happen in 8.9.x (if at all). So we should be safe to remove the cruft here. Phew!

Committed and pushed to 8.x-1.x.