Fix labels in Gitea issue templates

The Gitea labels have been updated from `type::Report` to `Type/Report`,
but the issue templates were still using the old style.

.gitea/issue_template/bug.yaml

@@ -1,9 +1,9 @@
 name: Bug Report
 about: File a bug report
 labels:
-  - "type::Report"
-  - "status::Needs Triage"
-  - "priority::Normal"
+  - "Type/Report"
+  - "Status/Needs Triage"
+  - "Priority/Normal"
 body:
   - type: markdown
     attributes:

.gitea/issue_template/design.yaml

@@ -1,7 +1,7 @@
 name: Design
 about: Create a design task (for developers only)
 labels:
-  - "type::Design"
+  - "Type/Design"
 body:
   - type: textarea
     id: body

.gitea/issue_template/todo.yaml

@@ -1,7 +1,7 @@
 name: To Do
 about: Create a to do task (for developers only)
 labels:
-  - "type::To Do"
+  - "Type/To Do"
 body:
   - type: textarea
     id: body