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_
            
splitted_grantees = [grantee.strip() for grantee in grantees.split(",")]
    for grantee in splitted_grantees:
        grantee_type, grantee_id = grantee.split("=")
        grantee_id = grantee_id.strip('"')
        if grantee_type not in ("uri", "id", "emailAddress"):
            ex = _create_invalid_argument_exc(
                "Argument format not recognized", get_header_name(grant), grantee
            )
            raise ex
        elif grantee_type == "uri" and grantee_id not in s3_constants.VALID_ACL_PREDEFINED_GROUPS:
            ex = _create_invalid_argument_exc("Invalid group uri", "uri", grantee_id)
            raise ex
        elif grantee_type == "id" and not is_valid_canonical_id(grantee_id):
            ex = _create_invalid_argument_exc("Invalid id", "id", grantee_id)
            raise ex
        elif grantee_type == "emailAddress":
            
            continue
def validate_acl_acp(acp: AccessControlPolicy) -> None:
    if acp is None or "Owner" not in acp or "Grants" not in acp:
        raise MalformedACLError(
            "The XML you provided was not well-formed or did not validate against our published schema"
        )
    if not is_valid_canonical_id(owner_id := acp["Owner"].get("ID", "")):
        ex = _create_invalid_argument_exc("Invalid id", "CanonicalUser/ID", owner_id)
        raise ex
    for grant in acp["Grants"]: