Issue #2278971 by mondrake, daffie, xjm, longwave: Deprecate Connection::supportsTransactions()

core/assets/scaffold/files/default.settings.php

core/lib/Drupal/Core/Database/Connection.php

core/lib/Drupal/Core/Database/Driver/mysql/Connection.php

core/lib/Drupal/Core/Database/Driver/pgsql/Connection.php

core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php

...content/tests/src/Functional/BlockContentCreationTest.php

core/modules/node/tests/src/Functional/NodeCreationTest.php

...tests/Drupal/KernelTests/Core/Database/ConnectionTest.php

...s/Drupal/KernelTests/Core/Database/DeleteTruncateTest.php

...ests/Drupal/KernelTests/Core/Database/InvalidDataTest.php

...ests/Drupal/KernelTests/Core/Database/TransactionTest.php

...sts/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php

sites/default/default.settings.php