Merge pull request #30193 from zverok/robust-postgres-duplicate-db

More robust PostgreSQL database duplication check

activerecord/lib/active_record/tasks/postgresql_database_tasks.rb

@@ -22,7 +22,7 @@ def create(master_established = false)
           configuration.merge("encoding" => encoding)
         establish_connection configuration
       rescue ActiveRecord::StatementInvalid => error
-        if /database .* already exists/.match?(error.message)
+        if error.cause.is_a?(PG::DuplicateDatabase)
           raise DatabaseAlreadyExists
         else
           raise