public DockerConfig getDockerConfig() throws HyscaleException {
            if (dockerConfig != null) {
                return dockerConfig;
            } else {
                build();
                return dockerConfig;
            }
        }
Returns credential helper if registry pattern found  in credHelpers if specified
or directly credsStore if specified else returns null.

@param pattern
@return docker credential helper else returns null
workflow-controller/controller-service/src/main/java/io/hyscale/controller/manager/impl/LocalRegistryManagerImpl.java