Going to page 2 on "list terms" page doesn't display additional terms

Problem/Motivation

Taxonomy terms that have more children than will fit on one page (>100) then when paging to next page term page becomes blank.

1. Create a new vocabulary (/admin/content/taxonomy/add/vocabulary)
2. Run drush ev '$config = \Drupal::configFactory()->getEditable("taxonomy.settings");$config->set('terms_per_page_admin', 3);$config->save(); or drush vset taxonomy_terms_per_page_admin 3' in D7, or modify drupal8\core\modules\taxonomy\config\install\taxonomy.settings.yml file manually, and change terms_per_page_admin to the value of 3.
3. Add 5 terms than will fit onto the "list terms" page.
4. Make sure that one parent has more than 100 children No need for this, if you modify the terms_per_page_admin value. Instead use the number you have set + 2.
5. On page one everything is working (screenshot 1)
6. Click on page 2 (or "next") on the "list terms" page
7. It will go to the the next page but says "No terms available."(screenshot 2)

The whole behavior and codebase is confusing.

Remaining tasks

**Fix page 2**
Patch in #33 gets terms to show on page two but they are the same terms from page 1.

**Write Tests**
Test needs to be written to verify.
-Generate 150 terms
-Set all terms to be a child of one term
-View admin/structure/taxonomy/[vocab]
-Verify terms are showing as children of parent on page 1
-Navigate to page 2 and ensure parent term shows again and other terms.
-Also ensure on page two that terms are different than page 1.

Original report by whatistocome

To re-produce issue:
* Create a new vocabulary (/admin/content/taxonomy/add/vocabulary)
* Add more terms than will fit onto the "list terms" page
* Click on page 2 (or "next") on the "list terms" page
* It will go to the the next page but says "No terms available."