private String tempOffsetsFile() {
            try {
                return TestUtils
                        .tempFile("connect-standalone-offsets", null)
                        .getAbsolutePath();
            } catch (IOException e) {
                throw new UncheckedIOException("Failed to create temporary offsets file", e);
            }
        }
Start a standalone embedded connect worker. Internally, this class will spin up a Kafka cluster,
set up any tmp directories. and clean them up on exit. Methods on the same
{@code EmbeddedConnectStandalone} are not guaranteed to be thread-safe.
connect/runtime/src/test/java/org/apache/kafka/connect/util/clusters/EmbeddedConnectStandalone.java