Issue #3124382 by mondrake, daffie, alexpott, catch: Remove per-table prefixing

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

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

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

core/modules/mysql/src/Driver/Database/mysql/Schema.php

core/modules/pgsql/src/Driver/Database/pgsql/Schema.php

.../modules/sqlite/src/Driver/Database/sqlite/Connection.php

core/modules/system/system.install

...onalTests/Installer/InstallerWithTablePrefixArrayTest.php

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

core/tests/Drupal/KernelTests/Core/Database/SchemaTest.php

...al/KernelTests/KernelTestBaseDatabaseDriverModuleTest.php

core/tests/Drupal/Tests/Core/Database/ConnectionTest.php