docs(BUG-REPORT.yml): make reproduction url optional

Author: georgeRobertson

.github/ISSUE_TEMPLATE/BUG-REPORT.yml

@@ -20,7 +20,7 @@ body:
       description: Please enter your GitHub URL to provide a reproduction of the issue
       placeholder: ex. https://github.com/USERNAME/REPO-NAME
     validations:
-      required: true
+      required: false
   - type: textarea
     id: reprod
     attributes: