### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

CopyObject API does not check precondition headers such as `x-amz-copy-source-if-modified-since`. Instead it seems to always copy the object.

### Expected Behavior

The API should return a 412 response with content similar to:

```
<Error><Code>PreconditionFailed</Code><Message>At least one of the pre-conditions you specified did not hold</Message><Condition>x-amz-copy-source-If-Modified-Since</Condition><RequestId>14HR9PXJRG5B1GR5</RequestId><HostId>HztBs2jYea1fzzPWo1JWy33NQJqo1S1IsK62rkbnVEI04PnGNCi8sPVrichGQxH3FQwLA2RIyF4=</HostId></Error>
```

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

    docker run localstack/localstack

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

```
aws s3  --profile localstack --endpoint-url http://s3.localhost.localstack.cloud:4566 \
  ls s3://net-amazon-s3-test/Makefile.am
2023-01-25 10:47:40        537 Makefile.am

aws s3api copy-object --copy-source net-amazon-s3-test/Makefile.am --key Makefile.am.2 \
  --bucket net-amazon-s3-test2 --profile localstack --endpoint-url http://s3.localhost.localstack.cloud:4566 \
  --copy-source-if-modified-since "Wed, 25 Jan 2023 16:16:27 GMT"
{
    "CopyObjectResult": {
        "ETag": "\"46ada9d1fe8f8a311ff4504c226e061c\"",
        "LastModified": "2023-01-25T16:18:43+00:00"
    }
}
```

### Environment

```markdown
- OS: penguin
- LocalStack: latest
```


### Anything else?

_No response_
aws_client.s3.put_(Bucket=s3_bucket, Key=key_name, Tagging="tag1=tag1")
        # GetO
        get__tagging_url = f"{bucket_url}/{key_name}?tagging"
        resp = s3_http_client.get(get__tagging_url, headers=headers)
        resp_dict = xmltodict.parse(resp.content)
        assert resp_dict["Tagging"]["TagSet"] == {"Tag": {"Key": "tag1", "Value": "tag1"}}
    @pytest.mark.aws_validated
    def test_s3_delete_s_trailing_slash(self, aws_http_client_factory, s3_bucket, aws_client):
        _key = "key-to-delete-trailing-slash"
        # crea
        aws_client.s3.put_(Bucket=s3_bucket, Key=_key, Body=b"123")
        headers = {"x-amz-content-sha256": "UNSIGNED-PAYLOAD"}
        s3_http_client = aws_http_client_factory("s3", signer_factory=SigV4Auth)
        # Endp
        bucket_url = f"{_bucket_url(s3_bucket)}/?delete&x-id=DeleteObjects"
        delete_body = f"""<Delete>
            <Object>
                <Key>{_key}</Key>
             </Object>
        </Delete>
        """
        # Post 
        resp = s3_http_client.post(bucket_url, headers=headers, data=delete_body)
        assert resp.status_code == 200
        resp_dict = xmltodict.parse(resp.content)
        assert "DeleteResult" in resp_dict
        assert resp_dict["DeleteResult"]["Deleted"]["Key"] == _key
    @pytest.mark.aws_validated
    @pytest.mark.xfail(reason="Behaviour not implemented yet")
    def test_complete_multipart_parts_checksum(self, s3_bucket, snapshot, aws_client):