Fix Snowflake tests - private access error (#11950)

Snowflake tests are still failing on develop branch. This time due to a `Private_Access` error. Attempting to fix that to make the tests on develop green.

distribution/lib/Standard/Snowflake/0.0.0-dev/src/Internal/Snowflake_Dialect.enso

@@ -223,7 +223,7 @@ type Snowflake_Dialect
        Add an extra cast to adjust the output type of aggregate operations.
        Some DBs do CAST(SUM(x) AS FLOAT) others do SUM(CAST(x AS FLOAT)).
     cast_aggregate_columns self op_kind:Text columns:(Vector Internal_Column) =
-        self.cast_op_type op_kind columns (SQL_Expression.Operation op_kind (columns.map c->c.expression))
+        self.cast_op_type op_kind columns (SQL_Expression.Operation op_kind (columns.map Internals_Access.column_expression))
 
     ## PRIVATE
     prepare_fetch_types_query : SQL_Expression -> Context -> SQL_Statement