docs(feature-request-template): add default labels (#62)

Author: laggage

.github/ISSUE_TEMPLATE/feature-request.yaml

@@ -1,5 +1,7 @@
 name: "新功能建议"
 description: 给vscode-cnb提一个新功能建议
+labels:
+  - "feature"
 
 body:
   - type: dropdown