HADOOP-17799. Improve the GitHub pull request template (#3277)

Reviewed-by: Yi Sheng <yisheng@apache.org>

.github/pull_request_template.md

@@ -1,6 +1,19 @@
-## NOTICE
+<!--
+  Thanks for sending a pull request!
+    1. If this is your first time, please read our contributor guidelines: https://cwiki.apache.org/confluence/display/HADOOP/How+To+Contribute
+    2. Make sure your PR title starts with JIRA issue id, e.g., 'HADOOP-17799. Your PR title ...'.
+-->
+
+### Description of PR
+
+
+### How was this patch tested?
+
+
+### For code changes:
+
+- [ ] Does the title or this PR starts with the corresponding JIRA issue id (e.g. 'HADOOP-17799. Your PR title ...')?
+- [ ] Object storage: have the integration tests been executed and the endpoint declared according to the connector-specific documentation?
+- [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0](http://www.apache.org/legal/resolved.html#category-a)?
+- [ ] If applicable, have you updated the `LICENSE`, `LICENSE-binary`, `NOTICE-binary` files?
 
-Please create an issue in ASF JIRA before opening a pull request,
-and you need to set the title of the pull request which starts with
-the corresponding JIRA issue number. (e.g. HADOOP-XXXXX. Fix a typo in YYY.)
-For more details, please see https://cwiki.apache.org/confluence/display/HADOOP/How+To+Contribute