Migrate some instrumentations

Author: sarahchen6

dd-java-agent/instrumentation/datastax-cassandra/datastax-cassandra-4.0/src/main/java/datadog/trace/instrumentation/datastax/cassandra4/CassandraClientInstrumentation.java

@@ -24,15 +24,6 @@ public String instrumentedType() {
     return "com.datastax.oss.driver.internal.core.session.DefaultSession";
   }
 
-  @Override
-  public String[] helperClassNames() {
-    return new String[] {
-      packageName + ".CassandraClientDecorator",
-      packageName + ".TracingSession",
-      packageName + ".ContactPointsUtil",
-    };
-  }
-
   @Override
   public void methodAdvice(MethodTransformer transformer) {
     transformer.applyAdvice(

dd-java-agent/instrumentation/google-http-client-1.19/src/main/java/datadog/trace/instrumentation/googlehttpclient/GoogleHttpClientInstrumentation.java

@@ -39,13 +39,6 @@ public String instrumentedType() {
     return "com.google.api.client.http.HttpRequest";
   }
 
-  @Override
-  public String[] helperClassNames() {
-    return new String[] {
-      packageName + ".GoogleHttpClientDecorator", packageName + ".HeadersInjectAdapter"
-    };
-  }
-
   @Override
   public void methodAdvice(MethodTransformer transformer) {
     transformer.applyAdvices(

dd-java-agent/instrumentation/jedis/jedis-4.0/src/main/java/datadog/trace/instrumentation/jedis40/JedisInstrumentation.java

@@ -33,13 +33,6 @@ public String instrumentedType() {
     return "redis.clients.jedis.Connection";
   }
 
-  @Override
-  public String[] helperClassNames() {
-    return new String[] {
-      "redis.clients.jedis.JedisClientDecorator",
-    };
-  }
-
   @Override
   public void methodAdvice(MethodTransformer transformer) {
     transformer.applyAdvice(

dd-java-agent/instrumentation/servlet/javax-servlet/javax-servlet-common/src/main/java/datadog/trace/instrumentation/servlet/http/HttpServletInstrumentation.java

@@ -45,13 +45,6 @@ public ElementMatcher<TypeDescription> hierarchyMatcher() {
     return extendsClass(named(hierarchyMarkerType()));
   }
 
-  @Override
-  public String[] helperClassNames() {
-    return new String[] {
-      "datadog.trace.instrumentation.servlet.SpanNameCache", packageName + ".HttpServletDecorator",
-    };
-  }
-
   /**
    * Here we are instrumenting the protected method for HttpServlet. This should ensure that this
    * advice is always called after Servlet3Instrumentation which is instrumenting the public method.

dd-java-agent/instrumentation/servlet/javax-servlet/javax-servlet-common/src/main/java/datadog/trace/instrumentation/servlet/http/HttpServletResponseInstrumentation.java

@@ -42,7 +42,6 @@ public ElementMatcher<TypeDescription> hierarchyMatcher() {
   public String[] helperClassNames() {
     return new String[] {
       "datadog.trace.instrumentation.servlet.ServletRequestSetter",
-      packageName + ".HttpServletResponseDecorator",
     };
   }