[Bug] - REST GetObjectAttributes - incorrect error message when attribute param is wrong

[lrm25]

Describe the bug
The following error message is reported when an attribute param is wrong in versitygw:

<?xml version="1.0" encoding="UTF-8"?>
   <Error><Code>InvalidRequest</Code><Message>The x-amz-object-attributes header specifying the attributes to be retrieved is either missing or empty</Message><Resource></Resource><RequestId></RequestId><HostId></HostId></Error>

This is incorrect, as the attribute isn't empty, it's wrong. Here's what is reported when going direct to s3:

<?xml version="1.0" encoding="UTF-8"?>
   <Error><Code>InvalidArgument</Code><Message>Invalid attribute name specified.</Message><ArgumentName>x-amz-object-attributes</ArgumentName><ArgumentValue>ETags</ArgumentValue><RequestId>QPXG94ABP0V5JE4K</RequestId><HostId>Y9IEVTI2VaHnOvbFZkdcvlKq6qyI9G/n6lPKzIl9SLY5Nqw4jnzaGlDWIt3kaXVLTP5pQFM5Mfs=</HostId></Error>

Note that this contains the invalid argument value "ETags" and an accurate error message.

To Reproduce

1. Start versitygw, e.g.: ./versitygw --access=******** --secret=******** --region=us-east-1 --iam-dir=/Users/lukemccrone/devel/versitygw/iam --cert /Users/lukemccrone/devel/versitygw/cert.pem --key /Users/lukemccrone/devel/versitygw/versitygw.pem posix --versioning-dir /tmp/versioning /tmp/gw
2. Create bucket, e.g.: aws --no-verify-ssl s3api create-bucket --bucket versity-gwtest-bucket-one-1
3. Add object, e.g.: aws --no-verify-ssl s3api put-object --body /Users/lukemccrone/devel/versitygw/versity-gwtest-files/test_file --bucket versity-gwtest-bucket-one-1 --key test_file
4. Attempt to get invalid attribute, e.g. (with the get_object_attributes.sh REST script): curl -ks -w %{http_code} https://localhost:7070/versity-gwtest-bucket-one-1/test_file?attributes= -H Authorization: AWS4-HMAC-SHA256 Credential=********/20241223/us-east-1/s3/aws4_request,SignedHeaders=host;x-amz-content-sha256;x-amz-date;x-amz-object-attributes,Signature=558f9cf8424268cf30447c14f1029a56a99422335808e7efe195b70c52dc73c1 -H x-amz-content-sha256: UNSIGNED-PAYLOAD -H x-amz-date: 20241223T203326Z -H x-amz-object-attributes: ETags -o /Users/lukemccrone/devel/versitygw/versity-gwtest-files/attributes.txt

Expected behavior
versitygw error matches the direct error

Server Version
Version : v1.0.9
Build : 91d3bbc
BuildTime: 2024-12-23_08:30:21PM
Darwin Lukes-MacBook-Pro.local 23.4.0 Darwin Kernel Version 23.4.0: Fri Mar 15 00:12:25 PDT 2024; root:xnu-10063.101.17~1/RELEASE_ARM64_T6030 arm64