unserialize() is insecure unless allowed classes are limited. Use a safe format like JSON or use the allowed_classes option

Kindly review patch.

Your patch is not wrong, but it's not necessary either. This is a test fixture which is used only when running tests on the testbot. The input is constrained and there is no way this specific usage poses a security vulnerability for any site that has honeypot installed.

Specifically, this exact usage of unserialize() in test fixtures is copied directly from core, so if you think this is a problem then please open up an issue for core Drupal and report it. That is where it needs to be fixed, because there are hundreds of contributed modules which copy this usage from core. Fixing it here without reporting it in the core queue would be irresponsible.

See
core/modules/system/tests/fixtures/update/drupal-8.update-test-schema-enabled.php
core/modules/system/tests/fixtures/update/drupal-8.update-test-semver-update-n-enabled.php
core/modules/ckeditor5/tests/fixtures/update/ckeditor5-3222756.php
core/modules/ckeditor5/tests/fixtures/update/ckeditor5-3259593.php

@arti_parmar: Did you open a core issue?