Fix upsert error on repeated timestamps

Ref: rails/rails#55960

Author: aidanharan

lib/active_record/connection_adapters/sqlserver/database_statements.rb

@@ -649,7 +649,7 @@ def joining_on_columns_with_uniqueness_constraints(columns_with_uniqueness_const
         # however, since we need to have "target." for the assignment, we also generate the CASE switch ourselves
         def build_sql_for_recording_timestamps_when_updating(insert:)
           insert.model.timestamp_attributes_for_update_in_model.filter_map do |column_name|
-            if insert.send(:touch_timestamp_attribute?, column_name)
+            if insert.send(:touch_timestamp_attribute?, column_name) && !column_name.to_sym.in?(insert.send(:insert_all).updatable_columns)
               "target.#{quote_column_name(column_name)}=CASE WHEN (#{insert.updatable_columns.map { |column| "(source.#{quote_column_name(column)} = target.#{quote_column_name(column)} OR (source.#{quote_column_name(column)} IS NULL AND target.#{quote_column_name(column)} IS NULL))" }.join(" AND ")}) THEN target.#{quote_column_name(column_name)} ELSE #{high_precision_current_timestamp} END,"
             end
           end.join