feat: Update issue template removing automatic assignment

Following ba4cb59 (feat: Add workflow to
notify admins by email of instance request), explicit assignment is not
needed.

.github/ISSUE_TEMPLATE/request.yml

@@ -2,8 +2,6 @@ name: Request Instance
 description: Issue template to request a cloud instance creation.
 title: "Instance: "
 assignees:
-  - jcfr
-  - muratmaga
 
 body:
   - type: markdown