Line number in CSV import error messages is incorrect

Description

Hello,

The error message from CSV import is not correct when we fail an import It mention the last valid line in place of the last line that failed.

Example:

import failed for line 68

But we had 68 correct import, it's the line 69 that failed

Distribution Name and Version

Ubuntu LTS

FusionDirectory Version

1.3-dev

Plugin with the defect

ldapmanager

PHP version used

7.0

Origin of php packages

Ubuntu

Steps to Reproduce

1. Create a CSV with an error
2. Import your csv

Expected behavior:

Mention the correct failed line

Actual behavior:

Mention an incorrect failed line

Reproduces how often: 100%