Constructs a RefreshingSessionAWSCredentials object.
AmazonSecurityTokenService is created from passed-in credentials and
config object and is used to refresh credentials.
Passed-in AWSCredentials cannot be session credentials.

C# |
public RefreshingSessionAWSCredentials( AWSCredentials stsCredentials, AmazonSecurityTokenServiceConfig stsConfig )

- stsCredentials (AWSCredentials)
- stsConfig (AmazonSecurityTokenServiceConfig)
- Config object used for the constructed AmazonSecurityTokenService.