Mention that typescript files are executed by sequelize

[PythonCoderAS]

Issue Creation Checklist

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Issue Description

What was unclear/insufficient/not covered in the documentation

The docs have no mention that migration files written in TypeScript are executed by sequelize. This has led to confusion because I would compile the .ts files to .js and then get confused as to why remove column operations would fail.

If possible: Provide some suggestion on how we can enhance the docs

Mention that typescript migration files are also run.

Additional context

N/A

[ephys]

PR welcome