Merge pull request #4 from humanmade/use-add-query-arg

Use `add_query_arg()` instead of `add_query_args()`

inc/class-provider.php

@@ -355,6 +355,6 @@ public function resize( WP_Post $attachment, int $width, int $height, $crop = fa
 			$query_args['crop'] = implode( ',', $crop );
 		}
 
-		return add_query_args( urlencode_deep( $query_args ), $base_url );
+		return add_query_arg( urlencode_deep( $query_args ), $base_url );
 	}
 }