Simplifying context

Co-authored-by: Aaron Jorbin <aaronjorbin@users.noreply.github.com>

Author: t-hamano

src/wp-admin/includes/class-wp-theme-install-list-table.php

@@ -345,7 +345,7 @@ public function single_row( $theme ) {
 			'<a class="install-theme-preview" href="%s" aria-label="%s">%s</a>',
 			esc_url( $preview_url ),
 			esc_attr( $preview_title ),
-			_x( 'Preview', 'verb, theme row action to preview a theme' )
+			_x( 'Preview', 'verb' )
 		);
 
 		/**