fix(Docker): add amr encoder (#7247)

- Modified Dockerfile to add amr encoder (use libavcodec-extra)

Author: WenqiOfficial

Dockerfile

@@ -12,6 +12,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     ca-certificates \
     bash \
     ffmpeg \
+    libavcodec-extra \
     curl \
     gnupg \
     git \