Add missing link to repo CoC in issue template (#157)

Signed-off-by: Kathryn Baldauf <k_baldauf@apple.com>

Author: katiewasnothere

.github/ISSUE_TEMPLATE/02-feature.yml

@@ -26,7 +26,7 @@ body:
     id: terms
     attributes:
       label: Code of Conduct
-      description: By submitting this issue, you agree to follow our [Code of Conduct](https://example.com). 
+      description: By submitting this issue, you agree to follow our [Code of Conduct](https://github.com/apple/container/blob/main/CONTRIBUTING.md). 
       options:
         - label: I agree to follow this project's Code of Conduct
           required: true