in src/main/java/com/amazonaws/neptune/auth/NeptuneSigV4SignerBase.java [108:112]
public NeptuneSigV4SignerBase(final String regionName,
final AWSCredentialsProvider v1AwsCredentialProvider,
final String serviceName) throws NeptuneSigV4SignerException {
this(regionName, V1toV2CredentialsProvider.create(v1AwsCredentialProvider), serviceName);
}