Fix Unsupported Operation Exception in Language Server (#854)

Updated the method setTrace() as empty in the interface LanguageServer.

Fixes #853

org.eclipse.lsp4j/src/main/java/org/eclipse/lsp4j/services/LanguageServer.java

@@ -122,6 +122,9 @@ default void cancelProgress(WorkDoneProgressCancelParams params) {
 	 */
 	@JsonNotification("$/setTrace")
 	default void setTrace(SetTraceParams params) {
-		throw new UnsupportedOperationException();
+		/**
+		 * The method default behaviour was to throw UnsupportedOperationException
+		 * Keeping as empty to avoid it.
+		 */
 	}
 }