Nintendo rolled out a Switch firmware update in early May, bumping the system up to Version 16.0.3. It then followed this up at the end of the same month with an update for this update.
Now, it seems another one has arrived for the same patch. As highlighted by dataminer 'OatmealDome' this is another "rebootless update". Like the previous one, this latest change also updates the "bad words list" on the system.
As the same source has previously mentioned, "rebootless updates" are "silently installed" on the Nintendo Switch, so you don't actually have to do anything yourself for this kind of update.