Gutenberg block templates with Advanced Custom Fields

plugin.php

<?php
/*
Plugin Name: Plugin
Version: 1.0
*/

add_action('acf/init', function() {
    // Check function exists.
    if( function_exists('acf_register_block_type') ) {

        // register a testimonial block.
        acf_register_block_type([
            'name'              => 'rating',
            'title'             => __('Rating'),
            'description'       => __(''),
            'render_template'   => plugin_dir_path( __FILE__ ) . 'template-rating.php',
            'category'          => 'widgets',
            'icon'              => 'admin-comments',
            'keywords'          => ['rating', 'rank', 'grade'],
        ]);
    }
});

template-rating.php

<?php
ob_start();
?>

<!-- wp:group {"style":{"spacing":{"padding":{"top":"0px","right":"0px","bottom":"0px","left":"0px"}}},"backgroundColor":"tertiary","layout":{"inherit":false}} -->
<div class="wp-block-group has-tertiary-background-color has-background" style="padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px">
    <!-- wp:group {"layout":{"type":"flex","flexWrap":"nowrap","justifyContent":"left"}} -->
    <div class="wp-block-group">
        <!-- wp:group {"style":{"border":{"radius":"0px"}},"layout":{"wideSize":"","contentSize":""}} -->
        <div class="wp-block-group" style="border-radius:0px">
            <!-- wp:heading {"textAlign":"right","level":6,"backgroundColor":"vivid-red","textColor":"background","fontSize":"tiny"} -->
            <h6 class="has-text-align-right has-background-color has-vivid-red-background-color has-text-color has-background has-tiny-font-size">A</h6>
            <!-- /wp:heading -->
        </div>
        <!-- /wp:group -->

        <!-- wp:paragraph {"align":"left","fontSize":"small"} -->
        <p class="has-text-align-left has-small-font-size">Rating</p>
        <!-- /wp:paragraph -->
    </div>
    <!-- /wp:group -->
</div>
<!-- /wp:group -->

<?php
echo do_blocks(ob_get_clean());