Fix python package name

Dockerfile

@@ -2,7 +2,7 @@ ARG DOTNET_VERSION=5.0
 
 FROM node:alpine as web-builder
 ARG JELLYFIN_WEB_VERSION=master
-RUN apk add curl git zlib zlib-dev autoconf g++ make libpng-dev gifsicle alpine-sdk automake libtool make gcc musl-dev nasm python \
+RUN apk add curl git zlib zlib-dev autoconf g++ make libpng-dev gifsicle alpine-sdk automake libtool make gcc musl-dev nasm python3 \
  && curl -L https://github.com/jellyfin/jellyfin-web/archive/${JELLYFIN_WEB_VERSION}.tar.gz | tar zxf - \
  && cd jellyfin-web-* \
  && yarn install \