Include the user_agent as a header when send the events to Jitsu (dotCMS#32560)

### Proposed Changes
* Send the user_agent inside the Jitsu Event header

Author: freddyDOTCMS

dotCMS/src/main/java/com/dotcms/jitsu/EventLogRunnable.java

@@ -9,11 +9,13 @@
 import com.dotcms.jitsu.EventsPayload.EventPayload;
 import com.dotmarketing.beans.Host;
 import com.dotmarketing.util.Logger;
+import com.dotmarketing.util.UtilMethods;
 import com.dotmarketing.util.json.JSONObject;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableMap;
 import io.vavr.control.Try;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.http.Header;
 import org.apache.http.HttpStatus;
 
 import javax.ws.rs.core.HttpHeaders;
@@ -127,9 +129,16 @@ private CircuitBreakerUrlBuilder getCircuitBreakerUrlBuilder(String url) {
 
 
     public Optional<Response<String>> sendEvent(final CircuitBreakerUrlBuilder builder, final EventPayload payload) {
-        final CircuitBreakerUrl postLog = builder
-                .setRawData(payload.toString())
-                .build();
+        final String userAgent = payload.contains(ValidAnalyticsEventPayloadAttributes.USER_AGENT_ATTRIBUTE_NAME) ?
+                payload.get(ValidAnalyticsEventPayloadAttributes.USER_AGENT_ATTRIBUTE_NAME).toString() : null;
+
+        final CircuitBreakerUrlBuilder circuitBreakerUrlBuilder = builder.setRawData(payload.toString());
+
+        if (UtilMethods.isSet(userAgent)) {
+            circuitBreakerUrlBuilder.setHeaders(Map.of(HttpHeaders.USER_AGENT, userAgent));
+        }
+
+        final CircuitBreakerUrl postLog = circuitBreakerUrlBuilder.build();
 
         return Optional.ofNullable(
                         Try.of(postLog::doResponse)

dotCMS/src/main/java/com/dotcms/jitsu/EventsPayload.java

@@ -44,6 +44,13 @@ public String toString() {
         public Object get(String key) {
             return jsonObject.get(key);
         }
+        public Object remove(String key) {
+            return jsonObject.remove(key);
+        }
+
+        public boolean contains(String key) {
+            return jsonObject.containsKey(key);
+        }
     }
 
 }