Apply alternative suggestion

Co-authored-by: Weston Ruter <[email protected]>

Author: huzaifaalmesbah

src/wp-includes/ms-settings.php

@@ -99,13 +99,11 @@
 	wp_load_core_site_options( $site_id );
 }
 
-if ( isset( $wpdb ) ) {
-	if ( isset( $table_prefix ) ) {
-		$wpdb->set_prefix( $table_prefix, false ); // $table_prefix can be set in sunrise.php.
-	}
-	$wpdb->set_blog_id( $current_blog->blog_id, $current_blog->site_id );
-	$table_prefix = $wpdb->get_blog_prefix();
-}
+assert( isset( $wpdb ) );
+assert( isset( $table_prefix ) );
+$wpdb->set_prefix( $table_prefix, false ); // $table_prefix can be set in sunrise.php.
+$wpdb->set_blog_id( $current_blog->blog_id, $current_blog->site_id );
+$table_prefix       = $wpdb->get_blog_prefix();
 $_wp_switched_stack = array();
 $switched           = false;