Fix: Fix column ignorance on import

[Koc]

Reproducer

1. create table with 2 columns
2. start import csv file with 3 columns (2 match to existing columns, 1 extra). Unselect "create new columns"
3. ignore 3rd column
4. import

Expected result: file imported, ignored column not imported

Actual result: http 500 with an error Call to a member function getId() on string in file '/var/www/html/apps/tables/lib/Service/ImportService.php' line 565

nextcloud-tables-ignorance-2026-08-08_23.04.30.mp4

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