Update br/backup-and-restore-storages.md

Co-authored-by: Aolin <[email protected]>

br/backup-and-restore-storages.md

@@ -149,7 +149,7 @@ When storing backup data in a cloud storage system, you need to configure authen
 
 Before backup, configure the following privileges to access the backup directory on S3.
 
-- Minimum privileges for TiKV and Backup & Restore (BR) to access the backup directories during backup: `s3:ListBucket`, `s3:GetObject`, `s3:DeleteObject`, `s3:PutObject` and `s3:AbortMultipartUpload`
+- Minimum privileges for TiKV and Backup & Restore (BR) to access the backup directories during backup: `s3:ListBucket`, `s3:GetObject`, `s3:DeleteObject`, `s3:PutObject`, and `s3:AbortMultipartUpload`
 - Minimum privileges for TiKV and BR to access the backup directories during restore: `s3:ListBucket`, `s3:GetObject`, `s3:DeleteObject`, and `s3:PutObject`. BR writes checkpoint information to the `./checkpoints` subdirectory under the backup directory. When restoring log backup data, BR writes the table ID mapping relationship of the restored cluster to the `./pitr_id_maps` subdirectory under the backup directory.
 
 If you have not yet created a backup directory, refer to [Create a bucket](https://docs.aws.amazon.com/AmazonS3/latest/userguide/create-bucket-overview.html) to create an S3 bucket in the specified region. If necessary, you can also create a folder in the bucket by referring to [Create a folder](https://docs.aws.amazon.com/AmazonS3/latest/userguide/using-folders.html).