Support for `MERGE WITH SCHEMA EVOLUTION`

[stevenayers-bge]

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Describe the feature

Add support for the new MERGE WITH SCHEMA EVOLUTION syntax available on the current and preview channel SQL Warehouse versions. https://docs.databricks.com/en/delta/update-schema.html#schema-evolution-syntax-for-sql.

This is especially useful if you need schema evolution on struct data types.

The change is quite easy SQL wise, but I don't know how you would want to expose the option... via on_schema_change?

[mi-volodin]

@stevenayers-bge Hi, just to be sure I understand correctly. What is the difference between running this and setting the parameter for the table?

Based on Databricks documentation there are no differences.

Some use case might be helpful.

[mi-volodin]

Fixed in #739