Switch to OO approach

I like the work in this ticket, I think it's the better solution for fixing the path validation issues in Drupal 10.

I do think it needs a little bit of work, (I'll be pushing code up after this). Some ideas that I'm adding:
- The variable should be called block_exclude_pages_excluded_pages. 'hide_pages' assumes that you're not using "negate" for example. The reason that the textarea is called "Pages" is because it could be pages that you're showing on OR pages you're hiding on. The field we're adding should then just be called "Excluded pages" which will work whether the pages are set to be negated or not.
- The original patch was not done in a git branch, it was applied against a release version.
- The evaluate code is very confusing, it took me quite a while to make sense of, therefore it will be harder to maintain. We don't have to repeat the code in the parent function, we could potentially just override the configuration['pages'] variable and evaluate again.
- We definitely need a script to update existing sites, and there will be a lot of documentation changes as the main idea of this module was to use the exclamation point.

I needed the work in this ticket, but the patch against 1.3.x no longer applies, and I didn't see a recent update in the issue fork on GitLab, so I did a bit of refactoring and have a working approach.

I've added a PHPUnit kernel test, but there's some things where I'm not exactly sure what the existing behavior is, so I need to validate that before finishing those tests. Anyway, here's my WIP.

And, here's an updated patch where I filled out the rest of the tests.

ELC → changed the visibility of the branch 3044281 to hidden.