Fix GET regression in s3.query

While #19079 fixed PUT requests, it broke GET... Thanks to @sebest, GET works again.

S3 integration still feels buggy. I should have written unit tests for S3, but sorry, not this time.

I've manually tested PUT, DELETE and GET. My test scenario:

```sh
echo foo > ~/foo.txt
BUCKET=my-bucket-1
salt-call s3.put bucket=$BUCKET local_file=~/foo.txt path=foo.txt -l debug
salt-call s3.get bucket=$BUCKET local_file=~/foo.txt path=foo.txt -l debug
salt-call s3.delete bucket=$BUCKET path=foo.txt -l debug
```