As reported in https://github.com/localstack/localstack/issues/6659#issuecomment-1630932643_, `HeadObject` does not respect `ChecksumMode`. 


```shell
at 09:31:57 ➜ AWS_DEFAULT_REGION=us-west-1 aws --endpoint-url=http://localhost:4566 s3api create-bucket --bucket test-bucket --create-bucket-configuration LocationConstraint=us-west-1
{
    "Location": "http://test-bucket.s3.localhost.localstack.cloud:4566/"
}

at 09:32:13 ➜ aws --endpoint-url=http://localhost:4566 s3api put-object --bucket test-bucket --key file.json --body README.md --checksum-algorithm SHA256
{
    "ETag": "\"4bb2f1387449d690bff6336ea255909c\"",
    "ChecksumSHA256": "bzOikXXMUqRTCrpVq7Pt7LjJ0fjR3ccUfM19S/gnfqA="
}

# SHA256 missing here
at 09:32:20 ➜ aws --endpoint-url=http://localhost:4566 s3api head-object --bucket test-bucket --key file.json --checksum-mode Enabled
{
    "AcceptRanges": "bytes",
    "LastModified": "2023-07-11T13:32:15+00:00",
    "ContentLength": 1455,
    "ETag": "\"4bb2f1387449d690bff6336ea255909c\"",
    "ContentType": "binary/octet-stream",
    "Metadata": {}
}
```

Note the equivalent response from S3 actual includes the SHA256 value

```shell
at 10:21:23 ➜ aws s3api head-object --bucket test-bucket --key file.json --checksum-mode Enabled
{
    "AcceptRanges": "bytes",
    "Expiration": "expiry-date=\"Thu, 13 Jul 2023 00:00:00 GMT\", rule-id=\"all\"",
    "LastModified": "2023-07-11T14:21:09+00:00",
    "ContentLength": 1956,
    "ChecksumSHA256": "bj7fqCqtaF95M1ULwQRDJuHbL/Xd9NVMH6pua9OINcc=",
    "ETag": "\"f4be535d45019a4408dd5369986919f8\"",
    "ContentEncoding": "",
    "ContentType": "binary/octet-stream",
   
    "Metadata": {},
    
}
```

_Originally posted by @bdurrani in https://github.com/localstack/localstack/issues/6659#issuecomment-1630932643_
            
"""
        Moto tries to parse the TagSet and then iterate of it, not checking if it returned something
        Potential to be an easy upstream fix
        """
        try:
            tags: Dict[str, str] = fn(*args, **kwargs)
            for key in tags:
                tags[key] = tags[key] if tags[key] else ""
        except TypeError:
            tags = {}
        return tags
    @patch(moto_s3_responses.S3Response._cors_from_body)
    def _fix_parsing_cors_rules(fn, *args, **kwargs) -> List[Dict]:
        """
        Fix parsing of CORS Rules from moto, you can set empty origin in AWS. Replace None by an empty string
        """
        cors_rules = fn(*args, **kwargs)
        for rule in cors_rules:
            if rule["AllowedOrigin"] is None:
                rule["AllowedOrigin"] = ""
        return cors_rules
    @patch(moto_s3_responses.S3Response.is_delete_keys)
    def s3_response_is_delete_keys(fn, self):
        """
        Old provider had a fix for a ticket, concerning 'x-id' - there is no documentation on AWS about this, but it is probably still valid
        original comment: Temporary fix until moto supports x-id and DeleteObjects (#3931)
        """
        return get_safe(self.querystring, "$.x-id.0") == "DeleteObjects" or fn(self)
    @patch(moto_s3_responses.S3ResponseInstance.parse_bucket_name_from_url, pass_target=False)
    def parse_bucket_name_from_url(self, request, url):