feat: Add post_process to SQLStream.get_records to match RESTStream functionality

[BuzzCutNorman]

Feature scope

Taps (catalog, state, stream maps, etc.)

Description

I would like to propose that the code from RESTStream.get_records which invokes the method post_process be added to SQLStream.get_records. This enables SQL Tap developers to work with records before they are sent off to a Target. One example use would be the encoding of records values.

Current RESTStream.get_records:

        for record in self.request_records(context):
            transformed_record = self.post_process(record, context)
            if transformed_record is None:
                # Record filtered out during post_process()
                continue
            yield transformed_record

Current SQLStream.get_records:

        with self.connector._connect() as conn:
            for record in conn.execute(query):
                yield dict(record._mapping)

Proposed SQLStream.get_records:

        with self.connector._connect() as conn:
            for record in conn.execute(query):
                transformed_record = self.post_process(dict(record._mapping))
                if transformed_record is None:
                    # Record filtered out during post_process()
                    continue
                yield transformed_record