test: --demo's smtp-password is disabled, with a note why

internal/provider/fake/seed.go

@@ -31,7 +31,8 @@ func Seed(st *store.Store, alice, admin string) {
 		{link: azure + "kv-breakglass.vault.azure.net/secrets/emergency-admin", account: admin, source: "sub-prod",
 			path: []string{"platform-prod", "kv-breakglass"}, star: true, note: "incidents only: tell #ops when used"},
 		{link: azure + "kv-shared-prod.vault.azure.net/secrets/smtp-password", account: alice, source: "sub-prod",
-			path: []string{"platform-prod", "kv-shared-prod"}, uses: 2, ago: 26 * time.Hour},
+			path: []string{"platform-prod", "kv-shared-prod"}, uses: 2, ago: 26 * time.Hour,
+			note: "migrated to Microsoft Graph sendMail; disabled, delete after Q4"},
 		{link: dbx + "app/storage-key", account: "Databricks", source: "dbx-prod",
 			path: []string{"prod", "app"}, star: true, uses: 3, ago: 5 * time.Hour},
 		// A subscription, for both accounts, and a repo's file.