fix lint

Signed-off-by: Ben Ye <[email protected]>

pkg/store/bucket_test.go

@@ -31,6 +31,7 @@ import (
 	"github.com/leanovate/gopter/prop"
 	"github.com/oklog/ulid"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 	promtest "github.com/prometheus/client_golang/prometheus/testutil"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/relabel"
@@ -2728,7 +2729,7 @@ func benchmarkBlockSeriesWithConcurrency(b *testing.B, concurrency int, blockMet
 	wg := sync.WaitGroup{}
 	wg.Add(concurrency)
 
-	dummyCounter := prometheus.NewCounter(prometheus.CounterOpts{})
+	dummyCounter := promauto.NewCounter(prometheus.CounterOpts{})
 	for w := 0; w < concurrency; w++ {
 		go func() {
 			defer wg.Done()