chore(workflow): set Issue types (#547)

Author: chenjiahan

.github/ISSUE_TEMPLATE/1-bug-report.en-US.yml

@@ -1,6 +1,7 @@
 name: '🐞 Bug Report'
 description: Report a Bug to Rslib
 title: '[Bug]: '
+type: Bug
 labels: ['🐞 bug']
 body:
   - type: markdown

.github/ISSUE_TEMPLATE/2-feature-request.en-US.yml

@@ -1,6 +1,7 @@
 name: '💡 Feature Request'
 description: Submit a new feature request to Rslib
 title: '[Feature]: '
+type: Enhancement
 labels: ['💡 feature']
 body:
   - type: markdown