fix: github issue template typo

.github/ISSUE_TEMPLATE/bug_report.yaml

@@ -1,6 +1,6 @@
 name: Bug Report
 description: Create a bug report to help us improve
-title: "[Bug]: "
+title: "[Bug] "
 body:
   - type: textarea
     id: desc

.github/ISSUE_TEMPLATE/feature_request.yaml

@@ -1,6 +1,6 @@
 name: Feature Request
 description: Suggest an idea for AppFlowy
-title: "[FR]: "
+title: "[FR] "
 body:
   - type: textarea
     id: desc