Update ffmpeg version in dockerfile

Author: HO-COOH

Dockerfile

@@ -16,7 +16,7 @@ RUN     apt-get -yqq update && \
 
 FROM base as build
 
-ENV         FFMPEG_VERSION=4.4 \
+ENV         FFMPEG_VERSION=8.0 \
             AOM_VERSION=v1.0.0 \
             FDKAAC_VERSION=0.1.5 \
             FONTCONFIG_VERSION=2.12.4 \