Override default filters that skip API checks on premium Git Updater plugins in private repositories.

api-check-git-updater-premium-plugins.php

<?php
/**
 * Plugin Name:          API Check Git Updater Premium Plugins
 * Plugin URI:           https://gist.github.com/afragen/b752eb5da399a55f5597780efbbd5230
 * Description:          This plugin is used to override default exclusion of skipping API checks for Git Updater premium plugins in private repositories.
 * Version:              0.1
 * Author:               Andy Fragen
 * License:              MIT
 * Requires at least:    5.2
 * Requires PHP:         7.1
 * Gist Plugin URI:      https://gist.github.com/afragen/b752eb5da399a55f5597780efbbd5230
 */

add_filter( 'gu_test_premium_plugins', '__return_true' );