Add mlflow package

[saimidu]

Issue #, if available:

Description of changes:
Add mlflow package to cpu and gpu dockerfiles for v2.0.0

Test result:

$ python -m pytest -n auto -m cpu -vv -rs -k "mlflow" --local-image-version $VERSION
================================================================= test session starts ==================================================================
platform linux -- Python 3.12.3, pytest-8.2.2, pluggy-1.5.0 -- /home/saimidu/miniconda3/envs/sagemaker-distribution/bin/python
cachedir: .pytest_cache
rootdir: /local/home/saimidu/sagemaker-distribution
configfile: pytest.ini
plugins: xdist-3.6.1, mock-3.14.0
8 workers [1 item]
scheduling tests via LoadScheduling

test/test_dockerfile_based_harness.py::test_dockerfiles_for_cpu[mlflow.test.Dockerfile-required_packages27]
[gw0] [100%] PASSED test/test_dockerfile_based_harness.py::test_dockerfiles_for_cpu[mlflow.test.Dockerfile-required_packages27]

=================================================================== warnings summary ===================================================================
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
../../../../home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426
  /home/saimidu/miniconda3/envs/sagemaker-distribution/lib/python3.12/site-packages/boltons/timeutils.py:426: DeprecationWarning: datetime.datetime.utcfromtimestamp() is deprecated and scheduled for removal in a future version. Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.fromtimestamp(timestamp, datetime.UTC).
    EPOCH_NAIVE = datetime.utcfromtimestamp(0)

src/utils.py:4
src/utils.py:4
src/utils.py:4
src/utils.py:4
src/utils.py:4
src/utils.py:4
src/utils.py:4
src/utils.py:4
  /local/home/saimidu/sagemaker-distribution/src/utils.py:4: DeprecationWarning: conda.cli.python_api is deprecated and will be removed in 24.9. Use `conda.testing.conda_cli` instead.
    import conda.cli.python_api

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
====================================================== 1 passed, 16 warnings in 380.90s (0:06:20) ======================================================

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[saimidu]

The cpu/gpu.env.in files are not up-to-date due to having incorrectly placed the additional_packages_env file in the 2.0.0_beta folder instead of 2.0.0. Fixing this now, and regenerating the images/files locally to push to PR branch.

[claytonparnell]

Tested install on top of 1.8 image; no dependency issues, 10MB total (uncompressed) change.

[balajisankar15]

Git is already present. we don't need that