Comment 18 for bug 1882248

per https://autopkgtest.ubuntu.com/packages/ffmpeg/bionic/amd64

1. ffmpeg 7:3.4.8-0ubuntu0.2 never passed autopkgtest before.
2. ffmpeg autopkgtest also been triggered by vim and failed at the same place.

above result is consistent with the fact that it's a regression by itself.