Fix bug: correct xml comment syntax of license header (#474)

* add license header and check workflow

Signed-off-by: YanxuanLiu <[email protected]>

* correct xml comment format

Signed-off-by: YanxuanLiu <[email protected]>

---------

Signed-off-by: YanxuanLiu <[email protected]>

Author: YanxuanLiu

examples/XGBoost-Examples/aggregator/assembly/assembly-no-scala.xml

@@ -1,16 +1,18 @@
-# Copyright (c) 2024, NVIDIA CORPORATION.
-#
-# 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.
+<!-- 
+ Copyright (c) 2024, NVIDIA CORPORATION.
+
+ 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.
+-->
 
 <assembly xmlns="http://maven.apache.org/ASSEMBLY/2.0.0"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"