[Go SDK] Add fake impulse for inputs in Xlang Transform

[riteshghorse]

Python External Transform requires producers of input PCollection in the expansion request. Currently, we just pass the transform to be expanded and its associated input and output in Expansion Request. This PR adds a fake impulse to each input PCollection so that Python External Transform can expand transforms from Go.

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[riteshghorse]

CC: @lostluck

[lostluck]

Run XVR_Flink PostCommit

[lostluck]

Run XVR_Dataflow PostCommit

[lostluck]

Run Go Flink ValidatesRunner

[lostluck]

Run Go PostCommit

[lostluck]

LGTM. I'll merge once we have the PostCommit tests passing.

[lostluck]

This should resolve the evident issue in #22931, but there's another Schema/Logical type issue that follows up after and blocks python still. Ritesh is looking into them still.

[lostluck]

Go Flink ValidatesRunner Tests

[riteshghorse]

Okay, it is affecting other tests. I'm going to filter this change only for python external transforms.

[riteshghorse]

Run XVR_Flink PostCommit

[codecov]

Codecov Report

Merging #23383 (dabe9f0) into master (c36077a) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master   #23383      +/-   ##
==========================================
- Coverage   73.40%   73.40%   -0.01%     
==========================================
  Files         718      718              
  Lines       95652    95630      -22     
==========================================
- Hits        70211    70194      -17     
+ Misses      24130    24125       -5     
  Partials     1311     1311              

Flag	Coverage Δ
go	50.87% <0.00%> (-0.02%)	⬇️

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

Impacted Files	Coverage Δ
sdks/go/pkg/beam/core/runtime/xlangx/expand.go	0.00% <0.00%> (ø)
.../python/apache_beam/testing/test_stream_service.py	88.09% <0.00%> (-4.77%)	⬇️
...python/apache_beam/runners/worker/worker_status.py	74.66% <0.00%> (-2.00%)	⬇️
...che_beam/runners/interactive/interactive_runner.py	90.06% <0.00%> (-1.71%)	⬇️
...ks/python/apache_beam/runners/worker/sdk_worker.py	88.62% <0.00%> (-0.48%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.30% <0.00%> (-0.13%)	⬇️
...dks/python/apache_beam/options/pipeline_options.py	94.34% <0.00%> (-0.03%)	⬇️
sdks/python/apache_beam/transforms/util.py	96.06% <0.00%> (ø)
...eam/runners/interactive/interactive_environment.py	92.02% <0.00%> (+0.30%)	⬆️
sdks/python/apache_beam/transforms/combiners.py	93.43% <0.00%> (+0.38%)	⬆️
... and 5 more

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[riteshghorse]

Run Go Flink ValidatesRunner

[riteshghorse]

Run Go PostCommit

[riteshghorse]

Run Go PreCommit

[riteshghorse]

Run XVR_Flink PostCommit

[riteshghorse]

Run XVR_Dataflow PostCommit

[riteshghorse]

Looks like the postcommit failure is due to timeout?
https://ci-beam.apache.org/job/beam_PostCommit_Go_PR/544/console#:~:text=11%3A23%3A21%20Build%20timed%20out%20(after%20150%20minutes).%20Marking%20the%20build%20as%20aborted.

@lostluck

[riteshghorse]

Run Go PostCommit

[riteshghorse]

Run Go PostCommit

[lostluck]

Run Go Postcommit

[riteshghorse]

TestWindowSums_GBK and TestValidateWindowedSideInputs fails in Job Pending stage on dataflow. Probably the timeout error

[lostluck]

The Postcommit failures are on unrelated pipelines and due to quota issues w/apache-beam-testing on Dataflow (ip addresses of all things). Approved and merging.