Migrate dd-trace-core groovy files to java part 8 (#11437)

Migrate dd-trace-core groovy files to java part 8

we migrate 8 tests:
 - CheckpointerTest
 - DataStreamsTransactionExtractorsTest
 - DataStreamsWritingTest
 - DefaultDataStreamsMonitoringTest
 - DefaultPathwayContextTest
 - SchemaBuilderTest
 - SchemaSamplerTest
 - TransactionContainerTest

address comments

fix forbidden apis

fix spotbugs

sleep in synchronized block

Co-authored-by: devflow.devflow-routing-intake <devflow.devflow-routing-intake@kubernetes.us1.ddbuild.io>

Author: jpbempel

dd-java-agent/testing/src/main/groovy/datadog/trace/agent/test/base/HttpServer.groovy

@@ -0,0 +1,13 @@
+package datadog.trace.agent.test.base;
+
+import java.net.URI;
+import java.util.concurrent.TimeoutException;
+
+public interface HttpServer {
+
+  void start() throws TimeoutException;
+
+  void stop();
+
+  URI address();
+}