[Misc] Add bug report template for Dragonwell

Reviewers: 三红, 梁希, 芳玺, 麦庶

Reviewed By: 三红, 梁希, 芳玺, 麦庶

Differential Revision: https://aone.alibaba-inc.com/code/D854033

.github/ISSUE_TEMPLATE/alibaba-dragonwell-bug-report.md

+---
+name: Alibaba Dragonwell bug report
+about: Create a report to help us improve
+title: "[Bug] A new bug"
+labels: ''
+assignees: ''
+
+---
+
+**Description**
+A clear and concise description of what the bug is.
+
+**Steps to Reproduce**
+Steps to reproduce the behavior:
+1. Save below snippet '...'
+2. Compile it with javac '....'
+3. Execute with VM options '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**JDK version**
+The output of `java -version` command
+
+**Execution environment**
+ - OS and version:
+ - CPU model:
+ - Number of CPU cores:
+ - Size of physical memory:
+ - Inside Linux container?
+   - Linux container name (docker, pouch, etc):
+   - Linux container version: