[alt-builder] Fix #2

alt-builder/Dockerfile

 FROM amd64/debian:bullseye
 RUN apt-get update && apt-get install -y wget gnupg && \
-	echo "deb http://apt.llvm.org/unstable/ llvm-toolchain-10 main" >> /etc/apt/sources.list && \
-	echo "deb-src http://apt.llvm.org/unstable/ llvm-toolchain-10 main" >> /etc/apt/sources.list && \
-	wget -O llvm.key "https://apt.llvm.org/llvm-snapshot.gpg.key" && apt-key add llvm.key && \
-	apt-get remove --purge -y wget gnupg && \
+	#echo "deb http://apt.llvm.org/unstable/ llvm-toolchain-10 main" >> /etc/apt/sources.list && \
+	#echo "deb-src http://apt.llvm.org/unstable/ llvm-toolchain-10 main" >> /etc/apt/sources.list && \
+	#wget -O llvm.key "https://apt.llvm.org/llvm-snapshot.gpg.key" && apt-key add llvm.key && \
+	#apt-get remove --purge -y wget gnupg && \
 	\
 	apt-get update && \
 	apt-get install -y g++ g++-10 clang++-10 lld-10 \
@@ -16,7 +16,5 @@ RUN apt-get update && apt-get install -y wget gnupg && \
 	apt-get clean && \
 	rm -rf /var/lib/apt/lists/* && \
 	\
-	ln -sf /usr/bin/g++-10 g++ && \
-	ln -sf /usr/bin/gcc-10 gcc && \
-	\
-	for file in /usr/bin/*-10; do ln -sf $file $(echo $file | sed 's/-10$//g'); done
+	ln -sf /usr/bin/g++-10 g++ && ln -sf /usr/bin/gcc-10 gcc
+	#for file in /usr/bin/*-10; do ln -sf $file $(echo $file | sed 's/-10$//g'); done