bodyfetcher.py: fixup unused variable
bodyfetcher.py: fixup unused variable

Meant to include the ValueError in a diagnostic message but don't.
Not likely that the message would be hugely informative anyway.
Just return implicit None.

Charcoal-SE/SmokeDetector,ArtOfCode-/SmokeDetector,Charcoal-SE/SmokeDetector,ArtOfCode-/SmokeDetector