service/s3/s3manager: Fix typos in docs (#2642)
service/s3/s3manager: Fix typos in docs (#2642)

Fixes typos in the S3 transfer manager's Batch docs.
yxd-hde/aws-sdk-go,jasdel/aws-sdk-go,yxd-hde/aws-sdk-go,aws/aws-sdk-go,yxd-hde/aws-sdk-go,yxd-hde/aws-sdk-go