[Vendor] Update go-redis to v8.5.0 (#13749)

* Update go-redis to v8.4.0

* github.com/go-redis/redis/v8  v8.4.0 -> v8.5.0

* Apply suggestions from code review

Co-authored-by: zeripath <art27@cantab.net>

* TODO

* Use the Queue termination channel as the default context for pushes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* missed one

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: zeripath <art27@cantab.net>

vendor/github.com/go-redis/redis/v8/cluster_commands.go

@@ -0,0 +1,25 @@
+package redis
+
+import (
+	"context"
+	"sync/atomic"
+)
+
+func (c *ClusterClient) DBSize(ctx context.Context) *IntCmd {
+	cmd := NewIntCmd(ctx, "dbsize")
+	var size int64
+	err := c.ForEachMaster(ctx, func(ctx context.Context, master *Client) error {
+		n, err := master.DBSize(ctx).Result()
+		if err != nil {
+			return err
+		}
+		atomic.AddInt64(&size, n)
+		return nil
+	})
+	if err != nil {
+		cmd.SetErr(err)
+		return cmd
+	}
+	cmd.val = size
+	return cmd
+}