Showing Featured Images on the Month View

singe-event.php

<?php
/**
 * Month Single Event
 * This file contains one event in the month view
 *
 * Override this template in your own theme by creating a file at [your-theme]/tribe-events/month/Single_Event.php
 *
 * @package TribeEventsCalendar
 *
 */

if ( ! defined( 'ABSPATH' ) ) {
	die( '-1' );
}

global $post;

/**
 * We build and gather information specific to the individual event prior to
 * the tribe_events_template_data() call to reduce the opportunities for 3rd
 * party code to call wp_reset_postdata() or similar, which can result in the
 * $post global referencing something other than the event we're interested
 * in.
 */
$day      = tribe_events_get_current_month_day();
$event_id = "{$post->ID}-{$day['daynum']}";
$link     = tribe_get_event_link( $post );
$title    = get_the_title( $post );

$image_src = '';
if ( function_exists( 'has_post_thumbnail' ) && has_post_thumbnail( $post->ID ) ) {
	$has_image = true;
	$image_arr = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'medium' );
	$image_src = $image_arr[0];
}
?>

<div id="tribe-events-event-<?php echo $event_id ?>" class="<?php tribe_events_event_classes() ?>" data-tribejson='<?php echo tribe_events_template_data( $post ); ?>'>
	<?php if ( ! empty( $image_src ) ) { ?> <a href="<?php echo esc_url( $link ) ?>" class="url"><img src="<?php echo esc_url( $image_src ); ?>"></a><?php } ?>
	<h3 class="tribe-events-month-event-title entry-title summary"><a href="<?php echo esc_url( $link ) ?>" class="url"><?php echo $title ?></a></h3>
</div><!-- #tribe-events-event-# -->