Markup inconsistency with WooCommerce on checkout page

[smeric]

Is your feature request related to a problem? Please describe.
A minor problem ! To stay consistent with WooCommerce markup on checkout page, a <h2> should be replaced with a <h3> in /public/class-local-pickup-time.php#L687

Describe the solution you'd like
echo wp_kses( '<div id="local-pickup-time-select"><h2>' . __( 'Pickup Time', 'woocommerce-local-pickup-time' ) . '</h2>', $allowed_html );
Should be replaced with :
echo wp_kses( '<div id="local-pickup-time-select"><h3>' . __( 'Pickup Time', 'woocommerce-local-pickup-time' ) . '</h3>', $allowed_html );

Describe alternatives you've considered
Well, to stay visualy consistent with displayed titles depending of you theme, you may use CSS instead of changing the markup. But this may be complicated for someone who does not know how to do that...
Something like : #local-pickup-time-select h2{ /* re-style as a h3. That will depend on used theme... */ }

Additional context
Add any other context or screenshots about the feature request here.