[D7] PostgreSQL queries that fail in a transaction break the entire transaction

Uploading an initial patch which combines these two commits:

https://git.drupalcode.org/project/drupal/-/commit/cf44d3882fabebd9ad4bb...

https://git.drupalcode.org/project/drupal/-/commit/7af90e5f30a9e6fc285c6...

and relevant changes from both commits / current D10 code. Some parts (like changes in DatabaseConnection_pgsql::query()) were a bit adapted to the D7 code, as we are missing a few refactoring commits and the code here is still a bit different as in D8/D10. Other than this, other changes should be practically the same as in commits/D10 code.

I have also backported a new test, which should pass.

Adding a tag for Framework manager review. We should review it carefully if there aren't any potential drawbacks of this backport. Thanks!

Nice!

Justification for inclusion into core:
1) has tests
2) passes tests
3) effective backport of solution already included in D8/9/10

Looks great @poker10. Amazing the work that you and mcdruid have done on the db abstraction layer, it's vastly improved in the past 2 years!

By and large, D7 minor upgrades in the past 5 years have been adding significant improvements with very little to no pain. It just doesn't get any easier than a D7 minor release upgrade.