feat: _read_gbq_colab creates hybrid session

[TrevorBergeron]

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Fixes #<issue_number_goes_here> 🦕

[tswast]

Let's wait for the benchmarks to run at least once before this change before merging it.

[TrevorBergeron]

Let's wait for the benchmarks to run at least once before this change before merging it.

changed to be disabled by default, but able to easily be switched by caller

[tswast]

I suspect you'll get unit tests failing because this parameter is in bigframes.pandas but not the session.

Now that we have the benchmarks going again, I think it'd be safe to remove the parameter.

[TrevorBergeron]

ok ,reverted

[tswast]

e2e failures

FAILED tests/system/large/blob/test_function.py::test_blob_transcribe[gemini-2.0-flash-lite-001-True]
FAILED tests/system/large/streaming/test_pubsub.py::test_streaming_df_to_pubsub

are unrelated.