docs: Fix reference to SQL QA migration (#25157)
**Description:** I found that the link to the notebook in the Migration
notes is broken, i found that it was linked to this file
https://github.com/langchain-ai/langchain/blob/v0.0.250/docs/extras/use_cases/tabular/sql_query.ipynb
and i think now this tutorial
https://github.com/JuanFKurucz/langchain/blob/master/docs/docs/tutorials/sql_qa.ipynb
is the best fit for this reference
**Twitter handle:** @juanfkurucz
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Co-authored-by: Chester Curme <chester.curme@gmail.com>
