changing displayed value on gerrit for build number not found case

BUG=b/239224440

Change-Id: Ic118ab55c51746af7dabbe7085db10a9d5986b02
Reviewed-on: https://cos-review.googlesource.com/c/cos/tools/+/35827
Cloud-Build: GCB Service account <228075978874@cloudbuild.gserviceaccount.com>
Reviewed-by: Arnav Kansal <rnv@google.com>
Tested-by: Arnav Kansal <rnv@google.com>
diff --git a/src/cmd/changelog-webapp/controllers/pageHandlers.go b/src/cmd/changelog-webapp/controllers/pageHandlers.go
index b38181e..470ca15 100644
--- a/src/cmd/changelog-webapp/controllers/pageHandlers.go
+++ b/src/cmd/changelog-webapp/controllers/pageHandlers.go
@@ -576,7 +576,13 @@
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
-	json.NewEncoder(w).Encode(map[string][]string{"versions": {buildData.BuildNum}})
+	versions := []string{}
+	if buildData.BuildNum == "0.000.0" {
+		versions = append(versions, "no build")
+	} else {
+		versions = append(versions, buildData.BuildNum)
+	}
+	json.NewEncoder(w).Encode(map[string][]string{"versions": versions})
 }
 
 func allowedOrigin(origin string) (string, bool) {