[skip ci]Update issue template (#4966)

Signed-off-by: Xiangyu Wang <xiangyu.wang@zilliz.com>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,13 +1,13 @@
 ---
-name: Bug report
+name: "\U0001F41B Bug report"
-about: Create a report to help us improve
+about: Create a bug report to help us improve Milvus
 title: ''
 labels: ''
 assignees: ''
 
 ---
 
-**Please state your issue using the following template in English.**
+**Please state your issue using the following template and, most importantly, in English.**
 
 **Describe the bug**
 A clear and concise description of what the bug is.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Ask a question
+    url: https://github.com/milvus-io/milvus/discussions
+    about: Ask questions and discuss with other community members

.github/ISSUE_TEMPLATE/documentation-request.md

@@ -0,0 +1,35 @@
+---
+name: "\U0001F4DD Documentation request"
+about: Report incorrect or needed documentation
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Please state your issue using the following template and, most importantly, in English.**
+
+**Location of incorrect documentation**
+Provide links and line numbers if applicable.
+
+**Describe the problems or issues found in the documentation**
+A clear and concise description of what you found to be incorrect.
+
+**Steps taken to verify documentation is incorrect**
+List any steps you have taken:
+
+**Suggested fix for documentation**
+Detail proposed changes to fix the documentation if you have any.
+
+---
+
+## Report needed documentation
+
+**Report needed documentation**
+A clear and concise description of what documentation you believe it is needed and why.
+
+**Describe the documentation you'd like**
+A clear and concise description of what you want to happen.
+
+**Steps taken to search for needed documentation**
+List any steps you have taken:

.github/ISSUE_TEMPLATE/enhancement.md

@@ -0,0 +1,15 @@
+---
+name: "Enhancement request"
+about: Suggest an enhancement idea for Milvus
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Please state your issue using the following template and, most importantly, in English.**
+
+**What would you like to be added ?**
+
+**Why is this needed ?**
+

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,13 +1,13 @@
 ---
-name: Feature request
+name: "\U0001F680 Feature request"
-about: Suggest an idea for this project
+about: Suggest an idea for Milvus
 title: ''
 labels: ''
 assignees: ''
 
 ---
 
-**Please state your issue using the following template in English.**
+**Please state your issue using the following template and, most importantly, in English.**
 
 **Is your feature request related to a problem? Please describe.**
 A clear and concise description of what the problem is. E.g. I wish I could use Milvus to do [...]