Update bug report and PR templates

Author: longquanzheng

.github/ISSUE_TEMPLATE/bug_report.md

@@ -6,6 +6,11 @@ labels: ''
 assignees: ''
 
 ---
+**Version of Cadence server, and client(which language)**
+This is very important to root cause bugs.
+- Server version: 
+- Client version:
+- Client langauge:
 
 **Describe the bug**
 A clear and concise description of what the bug is.

.github/pull_request_template.md

@@ -13,3 +13,8 @@
 <!-- Assuming the worst case, what can be broken when deploying this change to production? -->
 **Potential risks**
 
+<!-- Is it notable for release? e.g. schema updates, configuration or data migration required? If so, please mention it, and also update CHANGELOG.md -->
+**Release notes**
+
+<!-- Is there any documentation updates should be made for config, https://cadenceworkflow.io/docs/operation-guide/setup/ ? If so, please open an PR in https://github.com/uber/cadence-docs -->
+**Documentation Changes**