added steamcmd images and update buildx to latest

steamcmd/debian/Dockerfile

@@ -0,0 +1,27 @@
+FROM        --platform=$TARGETOS/$TARGETARCH debian:bullseye-slim
+
+LABEL       author="Matthew Penner" maintainer="matthew@pterodactyl.io"
+
+LABEL       org.opencontainers.image.source="https://github.com/pterodactyl/yolks"
+LABEL       org.opencontainers.image.licenses=MIT
+
+ENV         DEBIAN_FRONTEND=noninteractive
+
+RUN         dpkg --add-architecture i386 \
+            && apt update \
+            && apt upgrade -y \
+            && apt install -y tar curl gcc g++ lib32gcc-s1 libgcc1 libcurl4-gnutls-dev:i386 libssl1.1:i386 libcurl4:i386 lib32tinfo6 libtinfo6:i386 lib32z1 lib32stdc++6 libncurses5:i386 libcurl3-gnutls:i386 libsdl2-2.0-0:i386 iproute2 gdb libsdl1.2debian libfontconfig1 telnet net-tools netcat tzdata numactl \
+            && useradd -m -d /home/container container
+
+## install rcon
+RUN         cd /tmp/ \
+            && curl -sSL https://github.com/gorcon/rcon-cli/releases/download/v0.10.2/rcon-0.10.2-amd64_linux.tar.gz > rcon.tar.gz \
+            && tar xvf rcon.tar.gz \
+            && mv rcon-0.10.2-amd64_linux/rcon /usr/local/bin/
+
+USER        container
+ENV         USER=container HOME=/home/container
+WORKDIR     /home/container
+
+COPY        ./entrypoint.sh /entrypoint.sh
+CMD         [ "/bin/bash", "/entrypoint.sh" ]