add doc issue template: by create documentation.yml

.github/ISSUE_TEMPLATE/documentation.yml

@@ -0,0 +1,18 @@
+name: Docs
+description: For users or developers to report issues related to software documentation, such as missing or incomplete documentation, or documentation that is difficult to understand.
+labels: [Docs]
+assignees: Qiangqiang Gu
+body:
+- type: textarea
+  attributes:
+    label: Details
+    description: |
+      Please provide details about the documentation issue you are experiencing. Include any relevant information such as the specific section of the documentation, the information that is missing or unclear, and any suggestions for improvement. 
+    placeholder: |
+      Example: The documentation for the band structure calculations is missing. I have read the online manual, but I am still not sure how to do it. My suggestion is to add a new section to the online manual that describes this.
+  validations:
+      required: true
+- type: markdown
+  attributes:
+    value: >
+      Thank you for reporting this documentation issue. We will review and update the documentation as necessary. 📚