Added experimental annotation to fixes #22564

[ryanthompson591]

Adds experimental annotation to SklearnModelHandlerPandas and PytorchModelHandlerKeyedTensor.

New PTransforms that are experimental should be marked with an experimental annotation.
https://beam.apache.org/contribute/ptransform-style-guide/#compatibility

Though these are not PTransforms the annotation can generate warnings in logs.

fixes #22564

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[ryanthompson591]

R: @yeandy @tvalentyn

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[codecov]

Codecov Report

Merging #22565 (c45dd84) into master (48513ad) will increase coverage by 0.04%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master   #22565      +/-   ##
==========================================
+ Coverage   74.18%   74.22%   +0.04%     
==========================================
  Files         706      707       +1     
  Lines       93229    93299      +70     
==========================================
+ Hits        69159    69253      +94     
+ Misses      22802    22778      -24     
  Partials     1268     1268              

Flag	Coverage Δ
python	83.60% <50.00%> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...thon/apache_beam/ml/inference/pytorch_inference.py	0.00% <0.00%> (ø)
...thon/apache_beam/ml/inference/sklearn_inference.py	95.45% <100.00%> (+0.21%)	⬆️
sdks/python/apache_beam/utils/interactive_utils.py	95.12% <0.00%> (-2.44%)	⬇️
...hon/apache_beam/runners/direct/test_stream_impl.py	93.28% <0.00%> (-0.75%)	⬇️
...eam/runners/portability/fn_api_runner/execution.py	92.44% <0.00%> (-0.65%)	⬇️
...eam/runners/interactive/interactive_environment.py	91.71% <0.00%> (-0.31%)	⬇️
sdks/python/apache_beam/io/fileio.py	95.98% <0.00%> (-0.28%)	⬇️
sdks/python/apache_beam/io/filesystem.py	88.67% <0.00%> (-0.09%)	⬇️
sdks/python/apache_beam/io/aws/s3io.py	84.42% <0.00%> (ø)
sdks/python/apache_beam/io/gcp/gcsio.py	92.26% <0.00%> (ø)
... and 5 more

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[yeandy]

Can you remind me the behavior of this tag?

Do we need to remove this note from the docstring?

    **NOTE:** This API and its implementation are under development and
    do not provide backward compatibility guarantees.

[ryanthompson591]

@yeandy
This prints a message to the warning logs and doesn't modify doc strings.

[ryanthompson591]

@tvalentyn I just tested out doc generation. Good thing because there was an odd doc generation behavior. To get around it, I had to set all, which I think is something we should do anyhow.

The experimental annotation doesn't do anything with doc generation at this point, I don't think we need to add todo's or anything, because when/if someone does make a change, they will need to make modifications themselves at that piont.

[tvalentyn]

I had to set all,

I am not sure what you are referring to.

[ryanthompson591]

Run Python PreCommit

[tvalentyn]

Could you please check the failing test and file an issues if there is none filed at s.apache.org/beam-flakes ?

Thanks.