docker build failing on install emscripten layer

To reproduce:

docker build .

Unpacking '/opt/emsdk/zips/c630da9163a64e08de3dd948be0a0f7a175d285b-wasm-binaries.tbz2' to '/opt/emsdk/upstream'
Done installing tool 'releases-upstream-c630da9163a64e08de3dd948be0a0f7a175d285b-64bit'.
Running post-install step: npm ci ...
Running post-install step: npm install google-closure-compiler-linux
Done running: npm ci
Done installing SDK 'sdk-releases-upstream-c630da9163a64e08de3dd948be0a0f7a175d285b-64bit'.
Setting the following tools as active:
   node-12.18.1-64bit
   releases-upstream-c630da9163a64e08de3dd948be0a0f7a175d285b-64bit

Next steps:
- To conveniently access emsdk tools from the command line,
  consider adding the following directories to your PATH:
    /opt/emsdk
    /opt/emsdk/node/12.18.1_64bit/bin
    /opt/emsdk/upstream/emscripten
- This can be done for the current shell by running:
    source "/opt/emsdk/emsdk_env.sh"
- Configure emsdk in your bash profile by running:
    echo 'source "/opt/emsdk/emsdk_env.sh"' >> $HOME/.bash_profile
hack emscript config getter (em-config)
cp: cannot stat '/root/.emscripten': No such file or directory
The command '/bin/sh -c EMSDK_VERSION=1.39.2 &&     EMSDK_HASH=04d13b99d0630496139fa8f424c62aad65588c7b &&  mkdir -p /opt/emsdk &&  curl -sSL https://github.com/emscripten-core/emsdk/archive/${EMSDK_HASH}.tar.gz | tar zxf - -C /opt/emsdk --strip-components=1 &&   cd /opt/emsdk &&    ./emsdk update &&   ./emsdk install ${EMSDK_VERSION} &&     ./emsdk activate ${EMSDK_VERSION} &&    echo "hack emscript config getter (em-config)" &&   cp /root/.emscripten /home/${APP_USER}/.emscripten &&   printf '#!/usr/bin/env python\nimport os, sys\nexecfile(os.getenv("HOME")+"/.emscripten")\nprint eval(sys.argv[1])\n' >/usr/local/bin/em-config &&  chmod a+x /usr/local/bin/em-config' returned a non-zero code: 1

xiph / awcy

docker build failing on install emscripten layer #222