Source

File: wp-includes/functions.php

function wp_get_update_php_annotation() {
	$update_url  = wp_get_update_php_url();
	$default_url = wp_get_default_update_php_url();

	if ( $update_url === $default_url ) {
		return '';
	}

	$annotation = sprintf(
		/* translators: %s: Default Update PHP page URL. */
		__( 'This resource is provided by your web host, and is specific to your site. For more information, <a href="%s" target="_blank">see the official WordPress documentation</a>.' ),
		esc_url( $default_url )
	);

	return $annotation;
}