Removing a sql query with invalid syntax

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extra : source : 620700e4b1ecb2cc0b2a3f11e9051d415e5356fa
Changelog entry

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extra : source : 28301c20cd4117e6c7622b6b09cfc3f40870a52c
Invoice changes for product returns, on the db interface level.
UI components for returns
Merging 1.4 for merging back
Returns fixes and menu
Menu added to Pg-database.sql
Final fixes for returns.