message: Mirror "devel" and "latest-devel" tags
  Our old Dockerfile schema included "latest-devel" pointing to the devel tag specific to the latest TF release. Since our devel images now only target master, the "latest-devel" tag should point to the same image as "devel".
diff: @@ -40,7 +40,7 @@ releases:
  nightly:
  tag_specs:
  - "{nightly}{py}{jupyter}"
  - - "{ubuntu-devel}{py}"
  + - "{_TAG_PREFIX}{ubuntu-devel}{py}"
  # Built per-release and pushed to tensorflow/tensorflow
  # --arg _TAG_PREFIX=<val> should be set to "1.11" (for example) or "latest".
  