Resolve "(UBI) Error handling in ZTP component"

Closes #138 (closed)

src/ztp/src/main/java/org/etsi/tfs/ztp/exception/ExternalServiceFailureException.java

+/*
+* Copyright 2022-2023 ETSI TeraFlowSDN - TFS OSG (https://tfs.etsi.org/)
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package org.etsi.tfs.ztp.exception;
+
+public class ExternalServiceFailureException extends RuntimeException {
+
+    public ExternalServiceFailureException(String message, Exception e) {
+        super(message, e);
+    }
+
+    public ExternalServiceFailureException(String message) {
+        super(message);
+    }
+}