Say rotate's output on one line when the served rotation test fails (issue 1945)

cmd/mesh-controller/composed_served_integration_test.go

@@ -450,8 +450,9 @@ func TestServedARotationRewritesOnlyTheCompositionsThatUseIt(t *testing.T) {
 	storeKey, _ := sdkdelivery.ComposedKey("anchor", "store", fpOf('a'))
 	// The board's sealed credential file is new: its composition moves with the rotation.
 	if rev := m.waitForOrSay(t, "laptop", boardKey, before["laptop"][boardKey]); rev == 0 {
-		t.Fatalf("the board's composition did not move within a minute after the rotation; rotate said (holders before: %+v):\n%s\n%s",
-			holders, said, m.whatIsThere(t, "laptop"))
+		after, _ := m.open.inventory.HoldersOf(t.Context(), "postgres-database", "")
+		t.Fatalf("the board's composition did not move within a minute after the rotation; holders before %+v, after %+v; rotate said: %s; %s",
+			holders, after, strings.Join(strings.Fields(strings.ReplaceAll(said, "\n", " | ")), " "), m.whatIsThere(t, "laptop"))
 	}
 	moved := map[string]bool{}
 	for node, was := range before {