docker: golang default images now based on bullseye

Signed-off-by: deadprogram <ron@hybridgroup.com>

Dockerfile

@@ -2,8 +2,8 @@
 FROM golang:1.16 AS tinygo-base
 
 RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
-    echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster-11 main" >> /etc/apt/sources.list && \
-    apt-get update && apt-get clean && apt-get autoremove && \
+    echo "deb http://apt.llvm.org/bullseye/ llvm-toolchain-bullseye-11 main" >> /etc/apt/sources.list && \
+    apt-get update && \
     apt-get install -y llvm-11-dev libclang-11-dev lld-11 git
 
 COPY . /tinygo