Fix LP1029095, Acq: Receive Items on an Invoice does not work with Line Item Alerts

Fix LP1029095, Acq: Receive Items on an Invoice does not work with Line Item Alerts

1. Item reception was encountering a Javascript exception in the
check_lineitem_alerts() helper function, because there was a mismatch
between the input parameter name and the variable name actually used.

2. Also, took the opportunity to improve the performance of the for loop
to scan through alerts.

Signed-off-by: Bill Erickson <berick@esilibrary.com>