cannot build TFRA-enabled TF-serving binary for TFRA 0.8.0

[huangenyan]

When trying to complie the TFTA-enabled serving binary, I following the instructions in README, I use tensorflow/serving.git branch r2.16 according to the compatibility matrix:

## If enable GPU OPs
export SERVING_WITH_GPU=1 

## Specifiy the branch of TFRA
export TFRA_BRANCH="master" # The `master` and `r0.6` are available.

## Create workspace, modify the directory as you prefer to.
export TFRA_SERVING_WORKSPACE=~/tfra_serving_workspace/
mkdir -p $TFRA_SERVING_WORKSPACE && cd $TFRA_SERVING_WORKSPACE

## Clone the release branches of serving and TFRA according to `Compatibility Matrix`.
git clone -b r2.16 https://github.com/tensorflow/serving.git
git clone -b $TFRA_BRANCH https://github.com/tensorflow/recommenders-addons.git

## Run config shell script
cd $TFRA_SERVING_WORKSPACE/recommenders-addons/tools
bash config_tfserving.sh $TFRA_BRANCH $TFRA_SERVING_WORKSPACE/serving $SERVING_WITH_GPU

## Build serving with TFRA OPs.
cd $TFRA_SERVING_WORKSPACE/serving
./tools/run_in_docker.sh bazel build tensorflow_serving/model_servers:tensorflow_model_server

and encounter the following error:

Status: Image is up to date for tfra/serving:2.8.3-devel
docker.io/tfra/serving:2.8.3-devel
== Running cmd: sh -c 'cd /home/ec2-user/tfra_serving_workspace/serving; TEST_TMPDIR=.cache bazel build tensorflow_serving/model_servers:tensorflow_model_server'
$TEST_TMPDIR defined: output root default is '/home/ec2-user/tfra_serving_workspace/serving/.cache' and max_idle_secs default is '15'.
Starting local Bazel server and connecting to it...
ERROR: Traceback (most recent call last):
        File "/home/ec2-user/tfra_serving_workspace/serving/WORKSPACE", line 40, column 15, in <toplevel>
                versions.check("6.4.0")
        File "/home/ec2-user/tfra_serving_workspace/serving/.cache/_bazel_ec2-user/c41472d4aa52dc503a9f5911f5d7f7bc/external/bazel_skylib/lib/versions.bzl", line 105, column 13, in _check_bazel_version
                fail("Current Bazel version is {}; expected at least {}".format(
Error in fail: Current Bazel version is 3.7.2; expected at least 6.4.0
ERROR: error loading package '': Encountered error while reading extension file 'python/repositories.bzl': no such package
'@rules_python//python': error loading package 'external': Could not load //external package
INFO: Elapsed time: 7.755s
INFO: 0 processes.
FAILED: Build did NOT complete successfully (0 packages loaded)

I check the code in tools/config_tfserving.sh and find it uses a docker image on Dockerhub tfra/serving:2.8.3-devel as the compilation enviroment, but the environment doesn't support building 2.16 TF-serving app. Is it possible to add other images to support different versions?