satisfy full linter

pkg/es/doc.go

@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"math/rand/v2"
+	"strconv"
 	"strings"
 
 	"codeberg.org/scip/esctl/pkg/cfg"
@@ -45,7 +46,7 @@ func DocAdd(conf *cfg.Config, jsondoc string) error {
 		return fmt.Errorf("supplied document was not valid JSON: %w", err)
 	}
 
-	now := fmt.Sprintf("%d", rand.Int64())
+	now := strconv.FormatInt(rand.Int64(), 10)
 
 	res, err := conf.DefaultCluster.ES().Create(conf.Index, now).
 		Document(data).