Fix dismiss button in two WC admin notices

The dismiss button in the WC admin notices `legacy_shipping` and `no_shipping_methods` was not fully clickable due to a custom CSS applied to them. This custom CSS was used to add a background image to those notices. More specifically, the problem was caused by the use of `position: relative` applied to `<p>` elements. I couldn't find an easy way to fix this problem keeping the custom background image, so I opted to remove it to make the design of all notices identical (besides the background image, the custom CSS also added a few other differences to those to notices like the font size of the notice title).

assets/css/activation.scss

@@ -66,34 +66,3 @@ p.woocommerce-actions,
 .woocommerce-about-text {
 	margin-bottom: 1em !important;
 }
-
-div.woocommerce-legacy-shipping-notice,
-div.woocommerce-no-shipping-methods-notice {
-	overflow: hidden;
-	padding: 1px 12px;
-
-	p {
-		position: relative;
-		z-index: 1;
-		line-height: 1.5em;
-		margin: 12px 0;
-
-		&.main {
-			font-size: 1.1em;
-		}
-	}
-
-	&::before {
-		content: "\e01b";
-		font-family: "WooCommerce";
-		text-align: center;
-		line-height: 1;
-		color: #f7f1f6;
-		display: block;
-		width: 1em;
-		font-size: 20em;
-		top: 36px;
-		right: 12px;
-		position: absolute;
-	}
-}

includes/admin/views/html-notice-legacy-shipping.php

@@ -9,7 +9,7 @@
 	exit;
 }
 ?>
-<div id="message" class="updated woocommerce-message woocommerce-legacy-shipping-notice">
+<div id="message" class="updated woocommerce-message">
 	<a class="woocommerce-message-close notice-dismiss" href="<?php echo esc_url( wp_nonce_url( add_query_arg( 'wc-hide-notice', 'legacy_shipping' ), 'woocommerce_hide_notices_nonce', '_wc_notice_nonce' ) ); ?>">
 		<?php esc_html_e( 'Dismiss', 'woocommerce' ); ?>
 	</a>

includes/admin/views/html-notice-no-shipping-methods.php

@@ -9,7 +9,7 @@
 	exit;
 }
 ?>
-<div id="message" class="updated woocommerce-message woocommerce-no-shipping-methods-notice">
+<div id="message" class="updated woocommerce-message">
 	<a class="woocommerce-message-close notice-dismiss" href="<?php echo esc_url( wp_nonce_url( add_query_arg( 'wc-hide-notice', 'no_shipping_methods' ), 'woocommerce_hide_notices_nonce', '_wc_notice_nonce' ) ); ?>">
 		<?php esc_html_e( 'Dismiss', 'woocommerce' ); ?>
 	</a>