Remove sorter for "Credits?" column in purchasing batch row grid

too convoluted, and broken per recent sort overhaul

tailbone/views/purchasing/receiving.py

@@ -31,7 +31,6 @@ import logging
 from collections import OrderedDict
 
 import humanize
-import sqlalchemy as sa
 
 from rattail import pod
 from rattail.time import localtime, make_utc
@@ -1002,16 +1001,6 @@ class ReceivingBatchView(PurchasingBatchView):
             g.set_click_handler('invoice_unit_cost',
                                 'this.invoiceUnitCostClicked')
 
-        # credits
-        # note that sorting by credits involves a subquery with group by clause.
-        # seems likely there may be a better way? but this seems to work fine
-        Credits = self.Session.query(model.PurchaseBatchCredit.row_uuid,
-                                     sa.func.count().label('credit_count'))\
-                              .group_by(model.PurchaseBatchCredit.row_uuid)\
-                              .subquery()
-        g.set_joiner('credits', lambda q: q.outerjoin(Credits))
-        g.set_sorter('credits', Credits.c.credit_count)
-
         show_ordered = self.rattail_config.getbool(
             'rattail.batch', 'purchase.receiving.show_ordered_column_in_grid',
             default=False)