The template example products.xls (used in the import planner) references the
field "Vendors" (seller_ids) but was misspelled "Vendor" (renamed during new API
migration).
The file could no longer be imported.
Fixes#15159
SQL dump:
- Recent export with -O to remove owners
- correct poor Ramzy name
purchase order CSV:
- use correct column names
- remove destination and pricelist columns
- first file should not contain order lines
- second file should be same as first + lines