Add Linux `musl` builds

Hi

Just want to point out some findings: If you run YoutubeExplode in a docker container based on alpine, you cannot use the linux binaries from this repo.

I guess it's because they are linked against the glibc linker: Some hints

So, you have to install ffmpeg the alpine linux way like: apk add ffmpeg in your Dockerfile like so:

FROM mcr.microsoft.com/dotnet/aspnet:9.0-alpine

USER root

WORKDIR /tmp

RUN apk -q update && apk add -q ffmpeg && rm -rf /var/cache/*