bugfix - PR #180 - *Snowflake > Spark* Ensure matched inserts sync to snowflake

Ensure a new INSERT is synchronized to Snowflake, even when a match is already found.

## Motivation and Context
When a delta table is VACUUMed before a sync to Snowflake was triggered, a updated record will be considered as an "INSERT" record. However the target table might already contain this record. This PR ensures that this record is still updated as would be desired.

## How Has This Been Tested?
This was a bug in our code. This code currently lives in our repo and fixed the issue.

---------

Co-authored-by: Bruno De Deken <bruno.dedeken@nike.com>

Author: brunodd

src/koheesio/integrations/spark/snowflake.py

@@ -970,7 +970,7 @@ def _build_sf_merge_query(
             f"""
             MERGE INTO {target_table} target
             USING {stage_table} temp ON {key_join_string}
-            WHEN MATCHED AND temp._change_type = 'update_postimage'
+            WHEN MATCHED AND (temp._change_type = 'update_postimage' OR temp._change_type = 'insert')
                 THEN UPDATE SET {assignment_string}
             WHEN NOT MATCHED AND temp._change_type != 'delete'
                 THEN INSERT ({columns_string})

tests/spark/integrations/snowflake/test_sync_task.py

@@ -474,7 +474,7 @@ def test_merge_query_no_delete(self):
             """
             MERGE INTO target_table target
             USING tmp_table temp ON target.Country = temp.Country
-            WHEN MATCHED AND temp._change_type = 'update_postimage'
+            WHEN MATCHED AND (temp._change_type = 'update_postimage' OR temp._change_type = 'insert')
                 THEN UPDATE SET NumVaccinated = temp.NumVaccinated, AvailableDoses = temp.AvailableDoses
             WHEN NOT MATCHED AND temp._change_type != 'delete'
                 THEN INSERT (Country, NumVaccinated, AvailableDoses)
@@ -495,7 +495,7 @@ def test_merge_query_with_delete(self):
             """
             MERGE INTO target_table target
             USING tmp_table temp ON target.Country = temp.Country
-            WHEN MATCHED AND temp._change_type = 'update_postimage'
+            WHEN MATCHED AND (temp._change_type = 'update_postimage' OR temp._change_type = 'insert')
                 THEN UPDATE SET NumVaccinated = temp.NumVaccinated, AvailableDoses = temp.AvailableDoses
             WHEN NOT MATCHED AND temp._change_type != 'delete'
                 THEN INSERT (Country, NumVaccinated, AvailableDoses)