Missing [file] on line 355 in attachments controller #1303

Hello,

Not sure if this is intended. Was having issues uploading in media endpoint and found that the code on line 355 was looking like this:

$file = wp_handle_upload( $files, $overrides );

Changed it to:

$file = wp_handle_upload( $files['file'], $overrides );

Which fixed uploading issues for me(using form-data).