Remove the now obsolete design contest issue template

.github/ISSUE_TEMPLATE/design-contest.yml

@@ -1,44 +0,0 @@
-name: "PHP 8.5 Release Page Design Content Submission"
-description: "Submit your design for the PHP 8.5 Release Page"
-labels: ["Design Contest"]
-
-body:
-  - type: input
-    id: team
-    attributes:
-      label: "Names and Contact Details"
-      description: "Please provide your contact details"
-    validations:
-      required: true
-
-  - type: input
-    id: links
-    attributes:
-      label: "Link to mockup/prototype"
-      description: "Please provide a link to the mockup or prototype if available."
-      placeholder: "https://example.com/my-design.html"
-    validations:
-      required: true
-
-  - type: textarea
-    id: rationale
-    attributes:
-      label: "Rationale (300-600 words)"
-      description: |
-        Explain information hierarchy, layout choices, and how the design meets
-        goals. You must add 3 to 5 screenshots through "Paste, drop, or click
-        to add files".
-    validations:
-      required: true
-
-  - type: checkboxes
-    id: license
-    attributes:
-      label: "License"
-      description: |
-        Submissions must be original. If selected, I agree to license it under
-        the [same terms as the php.net website](https://www.php.net/copyright.php) and allow
-        adaptations for implementation.
-      options:
-        - label: "I confirm, and agree."
-          required: true