[BEAM-12308] change expected value in kakfa IT

[johnjcasey]

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[tvalentyn]

Run Python 3.8 PostCommit

[codecov]

Codecov Report

Merging #17740 (6065faa) into master (212d63d) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #17740      +/-   ##
==========================================
- Coverage   73.99%   73.99%   -0.01%     
==========================================
  Files         695      695              
  Lines       91798    91798              
==========================================
- Hits        67926    67924       -2     
- Misses      22624    22626       +2     
  Partials     1248     1248              

Flag	Coverage Δ
python	83.73% <ø> (-0.01%)	⬇️

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

Impacted Files	Coverage Δ
.../python/apache_beam/testing/test_stream_service.py	88.09% <0.00%> (-4.77%)	⬇️
...che_beam/runners/interactive/interactive_runner.py	89.20% <0.00%> (-1.44%)	⬇️
sdks/python/apache_beam/transforms/combiners.py	93.05% <0.00%> (-0.39%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.30% <0.00%> (-0.25%)	⬇️
sdks/python/apache_beam/transforms/util.py	96.06% <0.00%> (-0.16%)	⬇️
sdks/python/apache_beam/io/gcp/bigquery.py	64.99% <0.00%> (-0.12%)	⬇️
sdks/python/apache_beam/transforms/core.py	92.30% <0.00%> (ø)
...on/apache_beam/runners/dataflow/dataflow_runner.py	83.00% <0.00%> (+0.13%)	⬆️
...eam/runners/portability/fn_api_runner/execution.py	93.08% <0.00%> (+0.64%)	⬆️
...python/apache_beam/runners/worker/worker_status.py	79.71% <0.00%> (+1.44%)	⬆️
... and 1 more

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