fix(master): redirect a cancelled Check now instead of an empty response (#35)

internal/master/poller/poller_test.go

@@ -1070,6 +1070,15 @@ func TestPollServiceOnlyThisService(t *testing.T) {
 	require.Len(t, st.available, 1)
 	assert.Equal(t, int64(1), st.available[0].id)
 	assert.Equal(t, []string{ref}, reg.sortedCalls())
+	for _, c := range st.pollErrors {
+		assert.NotContains(t, c.ids, int64(2))
+	}
+	for _, c := range st.newer {
+		assert.Equal(t, int64(1), c.id)
+	}
+	for _, c := range st.lastTag {
+		assert.Equal(t, int64(1), c.id)
+	}
 }
 
 func TestPollServiceCancelled(t *testing.T) {