* feat: link stream to use _Connection and add unit tests

* docstring

* fix unit test in python 3.7

* add system test

* lint

* correct location for system test

* fix system test

* address comments

* use dict for closing connections

* switch back to use local variable for closed connections

* removed unused variable

* chore: Update gapic-generator-python to 1.23.6

PiperOrigin-RevId: 738170370

Source-Link: googleapis/googleapis@3f1e17a

Source-Link: googleapis/googleapis-gen@9afd8c3
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* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

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* feat: sample for AppendRowsStream with Arrow

* Update requirements.txt

* add test fixtures

* lint

* remove unused code

* correct fixtures

* add log for debugging

* remove debug code and small fixes

* remove fastavro in requirements.txt

* remove version for storage

* add print

* use schema in template and add table verification

* add a simple strategy to split large tables

* fix unit test

* wording

* add dependency

* address comments

* chore(main): release 2.30.0

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

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Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>