Bundled Themes: Add missing RTL styles for to fix inconsistent margins on .alignwide and .alignfull items.

Fixes the inconsistent margins for alignwide and alignfull classes used on Cover Block when it is the first block on a page.

This commit brings the changes from [47846] to the 5.4 branch.

Props kthmd, utz119, nikhilbhansi, and sabernhardt.
Fixes #49435.

Built from https://develop.svn.wordpress.org/branches/5.4@47847


git-svn-id: http://core.svn.wordpress.org/branches/5.4@47623 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-content/themes/twentytwenty/style-rtl.css

@@ -3508,6 +3508,11 @@ figure.wp-block-table.is-style-stripes {
 	margin: 4rem auto;
 }
 
+.post-inner .entry-content > .wp-block-cover.alignwide:first-child,
+.post-inner .entry-content > .wp-block-cover.alignfull:first-child {
+	margin-top: 0;
+}
+
 /* Font Families ----------------------------- */
 
 .entry-content {
@@ -5346,6 +5351,11 @@ a.to-the-top > * {
 		margin-right: 4rem;
 	}
 
+	.entry-content > .alignwide:first-child,
+	.entry-content > .alignfull:first-child {
+		margin-bottom: 8rem;
+	}
+
 	/* ENTRY MEDIA */
 
 	.alignfull > figcaption,

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4.2-alpha-47843';
+$wp_version = '5.4.2-alpha-47847';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.