I determined that the Guzzle6 adapter was not being used anymore, so I have bumped the Guzzle requirement to allow Drupal 10's Guzzle 7.5.0. I believe this should get us to full Drupal 10 compatibility.
The Project Update Bot also changed a few lines in the unit tests, but I suspect that would cause those tests to fail against older Drupal, so I have reverted those changes.
See comment here: https://www.drupal.org/project/search_api_pantheon/issues/3289519#comment-14789310
I determined that the Guzzle6 adapter was not being used anymore, so I have bumped the Guzzle requirement to allow Drupal 10's Guzzle 7.5.0. I believe this should get us to full Drupal 10 compatibility.
The Project Update Bot also changed a few lines in the unit tests, but I suspect that would cause those tests to fail against older Drupal, so I have reverted those changes.