It's interesting, because "chore" to me has strong connotations of "tedious, unpleasant".

Right. It derives from the idea that programmers are supposed to find "solving interesting problems" pleasant. On the other hand, boring, repetitive tasks are called "chores".

I don’t find it appropriate nor useful to place such a sentiment in a commit message, much less as a standard tag.

It's a nerdy colloquialism. ie, it's not that serious

That’s part of the reason why I’d object to it in a commit message, in a professional setting.

Some organizations strongly encourage marking all commits as one of a list of categories such as "feature/fix/chore/...". The tags are then bound to loose all meaning (literal or figurative) very soon.

Unless there was some "conspiracy" to violate the license (my original comment was an attempt at playfully hinting at that possibility, though I don't find it very likely), I'm sure the person who wrote that commit message thought about it for less than three seconds.