A backup of another sourcename with the same prefix is restored.

[Yohei Watanabe]

Describe the bug
If there are backups with sourcename xx-1 and xx-11, restoring by specifying xx-1 and after the last date and time of the xx-1 backup will restore xx-11.

Expected behavior
If sourcename is xx-1, only the backup of xx-1 is restored.

Additional context
Backup paths xx-1 and xx-11 are both listed because the object is retrieved by prefix.

moco/pkg/bucket/s3.go

Lines 112 to 120 in 1e5089d

 func (b s3Bucket) List(ctx context.Context, prefix string) ([]string, error) { 
 	li := &s3.ListObjectsV2Input{ 
 		Bucket: &b.name, 
 	} 
 	if len(prefix) > 0 { 
 		li.Prefix = &prefix 
 	} 
  
 	p := s3.NewListObjectsV2Paginator(b.client, li) 

[morimoto-cybozu]

Resolved by #648.