message: Define RHEL_ALLOW_PYTHON2_FOR_BUILD in Dockerfile.product
  This is required for building with python2 for RHEL 8.
diff: @@ -29,6 +29,7 @@ ENV CHROMEDRIVER_SKIP_DOWNLOAD=true \
  GECKODRIVER_SKIP_DOWNLOAD=true \
  SKIP_SASS_BINARY_DOWNLOAD_FOR_CI=true \
  CYPRESS_INSTALL_BINARY=0 \
  + RHEL_ALLOW_PYTHON2_FOR_BUILD=1 \
  NPM_CONFIG_TARBALL=$HOME/node-v12.16.1-headers.tar.gz
  # run the build
  