Allow usage of angle brackets in a site title or tagline.

The whole string is escaped with `esc_html()` anyway, so we don't
need to `wp_kses_post()`. This is a better experience for users who
want to use angle brackets in their site title or description.
Does not allow any HTML, adds unit tests.

props BandonRandon, pauldewouters.
fixes #27942.

Built from https://develop.svn.wordpress.org/trunk@35788


git-svn-id: http://core.svn.wordpress.org/trunk@35752 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/formatting.php

@@ -3706,7 +3706,6 @@ function sanitize_option( $option, $value ) {
 			if ( is_wp_error( $value ) ) {
 				$error = $value->get_error_message();
 			} else {
-				$value = wp_kses_post( $value );
 				$value = esc_html( $value );
 			}
 			break;