Fixed Rails Save Bang offenses in few spec/models/* files

This change was first introduced in merge request
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/61961.

Changelog: fixed

changelogs/unreleased/issue-220040-fix-robocop-savebang-spec-models-1.yml

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-title: Fixed Rails Save Bang offenses in few spec/models/* files
-merge_request: 61961
-author: Suraj Tripathi @surajtripathy07
-type: fixed