Update image to bookworm

Dockerfile

@@ -1,4 +1,4 @@
-FROM debian:buster
+FROM debian:bookworm
 
 # Create steam user 
 RUN useradd -m -d /home/steam steam
@@ -8,10 +8,11 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
     apt-get update && \
     apt-get install --yes -qq --no-install-recommends \
         curl \
-	lib32gcc1 \
-	lib32stdc++6 \
-	unzip \
-	git && \
+        ca-certificates \
+        lib32gcc1 \
+        lib32stdc++6 \
+        unzip \
+        git && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*