Replace '%s' in rm tests

Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: jfrazelle)

integration-cli/docker_cli_rm_test.go

@@ -102,7 +102,7 @@ func TestRmContainerOrphaning(t *testing.T) {
 		t.Fatalf("%v: %s", err, out)
 	}
 	if !strings.Contains(out, img1) {
-		t.Fatalf("Orphaned container (could not find '%s' in docker images): %s", img1, out)
+		t.Fatalf("Orphaned container (could not find %q in docker images): %s", img1, out)
 	}
 
 	deleteAllContainers()