ODS Style: improve "sheet per report section" option
erp5_ods_style supports sheet_per_report_section
option when rendering a report so that each report section is rendered in a different sheet in the result spreadsheet. In this MR we address two issues:
- The report header was not displayed at all. It is now displayed at the end, in a different sheet.
- sheet_per_report_section was not working at all when erp5_deferred_style was used.