Fix counting of frequently visited projects / groups

What does this MR do?

In !32628 (merged), the initialization of the frequent items component was deferred to when the dropdown is opened. Because we count visits in the created() hook of the component, this led to a bug where visits were not counted unless the user opens the dropdown.

This moves the initialization so that it works just like before.

Related to #23575

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
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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
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Security

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