Add a div after the site branding div

gistfile1.txt

/**
 * Site Title / Logo
 *
 * @since 1.0.0
 */
function astra_site_branding_markup() {
	?>
	<div class="site-branding">
		<div
		<?php
			echo astra_attr(
				'site-identity',
				array(
					'class' => 'ast-site-identity-das',
				)
			);
		?>
		>
			<?php astra_logo(); ?>
		</div>
	</div>
	<div>
		MY text
	</div>
	<!-- .site-branding -->
	<?php
}
add_action( 'astra_masthead_content', 'astra_site_branding_markup', 8 );