[CI] Fix typo in self_test_ltv.prm which causes errors in long self test and coverage test

• Related issues: #928 (closed)
• Requested reviewers: @kiene

Reason why this change is needed

• Long self test and coverage tests currently fail.

Description of the change

• Remove typo -fer 5 argument.

Affected operating points

• None, just CI

Related to #928 (closed)