fix(test): Label.Name is a plain string in go-github v89

The rebase onto main picked up the go-github v89 bump, which changed
Label.Name from *string to string. Adjust the PR read conformance
fixture accordingly.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: olaservo

pkg/github/output_conformance_pull_request_read_test.go

@@ -59,7 +59,7 @@ func TestPullRequestReadOutputValidatesAgainstDeclaredSchema(t *testing.T) {
 			Ref: gogithub.Ptr("main"),
 			SHA: gogithub.Ptr("ef567890"),
 		},
-		Labels:             []*gogithub.Label{{Name: gogithub.Ptr("bug")}},
+		Labels:             []*gogithub.Label{{Name: "bug"}},
 		Assignees:          []*gogithub.User{{Login: gogithub.Ptr("octocat")}},
 		RequestedReviewers: []*gogithub.User{{Login: gogithub.Ptr("reviewer")}},
 		Additions:          gogithub.Ptr(10),