[DO NOT MERGE] Test if sccache is the cause build flaky

Author: tesuji

src/ci/docker/dist-aarch64-linux/Dockerfile

@@ -21,9 +21,6 @@ RUN ./build-toolchains.sh
 
 USER root
 
-COPY scripts/sccache.sh /scripts/
-RUN sh /scripts/sccache.sh
-
 ENV PATH=$PATH:/x-tools/aarch64-unknown-linux-gnueabi/bin
 
 ENV CC_aarch64_unknown_linux_gnu=aarch64-unknown-linux-gnueabi-gcc \