Migrate table_pagination specs to Jest & VTU

What does this MR do?

This migrates the Karma-based spec spec/javascripts/vue_shared/components/table_pagination_spec.js to Jest and Vue Test Utils. All the assertions are the same but have been rewritten with Jest's and VTU's APIs.

This lays the groundwork for the upcoming changes to app/assets/javascripts/vue_shared/components/pagination/table_pagination.vue where we'll soon start using GitLab UI's pagination component instead of the custom one that's currently being used: !18602 (merged)

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers