[BEAM-14436] Adds code reviewers for GCP I/O connectors and KafkaIO to Beam OWNERS files

[chamikaramj]

Also updates the connector code to suggest using these reviewers for any significant changes to these connectors.

This will help reduce future regressions related to these connectors.

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[chamikaramj]

R: @aaltay

[codecov]

Codecov Report

Merging #17581 (88fcddb) into master (39de4b2) will increase coverage by 0.08%.
The diff coverage is 100.00%.

❗ Current head 88fcddb differs from pull request most recent head 9f09edc. Consider uploading reports for the commit 9f09edc to get more accurate results

@@            Coverage Diff             @@
##           master   #17581      +/-   ##
==========================================
+ Coverage   73.85%   73.93%   +0.08%     
==========================================
  Files         690      691       +1     
  Lines       91227    91562     +335     
==========================================
+ Hits        67373    67698     +325     
- Misses      22621    22631      +10     
  Partials     1233     1233              

Flag	Coverage Δ
python	83.71% <100.00%> (+0.06%)	⬆️

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

Impacted Files	Coverage Δ
sdks/python/apache_beam/io/gcp/bigquery.py	63.87% <ø> (ø)
.../apache_beam/io/gcp/datastore/v1new/datastoreio.py	86.16% <ø> (ø)
sdks/python/apache_beam/io/gcp/gcsio.py	92.26% <ø> (ø)
sdks/python/apache_beam/io/gcp/pubsub.py	90.65% <ø> (ø)
sdks/python/apache_beam/io/gcp/gcsfilesystem.py	88.23% <100.00%> (ø)
.../python/apache_beam/testing/test_stream_service.py	88.09% <0.00%> (-4.77%)	⬇️
...s/interactive/dataproc/dataproc_cluster_manager.py	84.21% <0.00%> (-3.70%)	⬇️
sdks/python/apache_beam/coders/row_coder.py	94.49% <0.00%> (-2.65%)	⬇️
sdks/python/apache_beam/runners/common.py	87.94% <0.00%> (-2.33%)	⬇️
...che_beam/runners/interactive/interactive_runner.py	89.20% <0.00%> (-1.64%)	⬇️
... and 27 more

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[aaltay]

Thank you!

[aaltay]

Run Python PreCommit

[aaltay]

Run Spotless PreCommit

[aaltay]

spotless failure may not be a flake, could you check that and self merge after that?

[chamikaramj]

Thanks!

[chamikaramj]

Run Spotless PreCommit