Add ORC support to GCSToBigQueryOperator and test for external tables

[Shashwatpandey4]

This PR adds support for the ORC source format to the GCSToBigQueryOperator.

Changes

• Updated GCSToBigQueryOperator to accept source_format="ORC"
• Added a unit test to validate ORC format works with external tables

This closes: #48624

Checklist

• Code change includes tests
• Verified DAG parsing and task execution locally
• Added test: test_external_table_should_accept_orc_source_format

[boring-cyborg]

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[bugraoz93]

Thanks for the changes!

[bugraoz93]

Seems like pre-commits need a rerun :)

[Shashwatpandey4]

i re-run the pre-commits @bugraoz93

[bugraoz93]

I think you need a rebase now because there is a commit from already merged PR. Try rebase and force push. Requesting a change to prevent merge the same commit

[Shashwatpandey4]

done @bugraoz93

[bugraoz93]

@Shashwatpandey4 I still can see Vincents' commit message :( Maybe easiest is creating a new PR and close this one

[Shashwatpandey4]

@bugraoz93 here's a new pr with only my changes in it 49188