docs: public static synchronized STSSessionCredentialsProvider getSessionCredentialsProvider(AWSCredentials longTermCredentials,
                                                                                             String serviceEndpoint,
                                                                                             ClientConfiguration stsClientConfiguration) {
          Key key = new Key(longTermCredentials.getAWSAccessKeyId(), serviceEndpoint);
          if ( !cache.containsKey(key) ) {
              cache.put(key, new STSSessionCredentialsProvider(longTermCredentials, stsClientConfiguration));
          }
          return cache.get(key);
      }