anki crashes when anki-wiktionary plugin

Hi,

I've observed that if `anki-wiktionary` cannot find a word while bulk-filing a *single* note, it throws a meaningful error.
However, if it used on multiple nodes and one of them fails, the `anki` in its entirety just crashes w/o further errors.

I'm not sure how much this is `anki`s fault or this plugin, but maybe the error handling in that case should be done more subtly?

I'm happy to file a bug at `anki` if you think this cannot reasonably be fixed within `anki-wiktionary`. I'm currently not involved deeply enough to figure it out myself. And maybe it is trivial and was just overlooked :)