Create concurrent index for pipeline_id_convert_to_bigint

What does this MR do and why?

As titled, this is the step of creating indexes.

It's to create the index for ci_pipeline_chat_data.pipeline_id_convert_to_bigint as the foreign key constraint requires the index so that we can later swap pipeline_id_convert_to_bigint with pipeline_id

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Related to #422821 (closed)