Plugins: Visually align plugin cards in Plugin Install screen.

This changeset adds a flexible CSS columns layout to plugin cards in the Plugin Install screen, to ensure plugin cards all have the same height.

Props jamesckemp, audrasjb, joyously, sabernhardt, sharjeelkhanvmi, joyously.
Fixes #55721.
See #55272.

Built from https://develop.svn.wordpress.org/trunk@54149

wp-admin/css/list-tables-rtl.css

@@ -1399,6 +1399,17 @@ ul.cat-checklist {
 	content: "\f147";
 }
 
+.plugin-install-php #the-list {
+	display: flex;
+	flex-wrap: wrap;
+}
+
+.plugin-install-php .plugin-card {
+	display: flex;
+	flex-direction: column;
+	justify-content: space-between;
+}
+
 .plugin-install-php h2 {
 	clear: both;
 }

wp-admin/css/list-tables.css

@@ -1398,6 +1398,17 @@ ul.cat-checklist {
 	content: "\f147";
 }
 
+.plugin-install-php #the-list {
+	display: flex;
+	flex-wrap: wrap;
+}
+
+.plugin-install-php .plugin-card {
+	display: flex;
+	flex-direction: column;
+	justify-content: space-between;
+}
+
 .plugin-install-php h2 {
 	clear: both;
 }

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-54148';
+$wp_version = '6.1-alpha-54149';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.