Deduplicate entries in History Menu

[ayoy]

Task/Issue URL: https://app.asana.com/0/0/1209328755192084/f

Description:
This change updates History Menu to only display one item per URL per day,
which is in line with other mainstream browsers. This change remains behind historyView
feature flag and will only be made available when Full History View is released.
The grouping logic was extracted into HistoryGroupingProvider class where
it's made dependent on the feature flag state. Current behavior remains unchanged,
as evidenced by added unit tests.

Steps to test this PR:

1. Run the app from Xcode and burn all data.
2. Visit a url (ideally one that doesn't redirect anywhere else).
3. Duplicate a tab a couple of times.
4. Open Main Menu -> History and verify that your URL is present there a couple of times (equal to the number of visits to the URL).
5. Select Main Menu -> Debug -> Feature Flag Overrides -> historyView to enable History View, and verify that the URL is only shown once in History View.
6. Visit some URL (a.k.a. URL A).
7. Visit another URL (a.k.a. URL B).
8. Refresh URL A, refresh URL B, refresh URL A, refresh URL B, etc...
9. Verify that History Menu shows alternating URLs A, B, A, B (with the most recently visited on top).
10. Enable historyView feature flag and verify that History Menu only contains 1 item with URL A and 1 item with URL B (with the most recently visited on top).
11. Go to History Menu -> Today -> Clear This History..., then confirm removing history and verify that all history from Today is gone (menu is empty).

Definition of Done:

• Does this PR satisfy our Definition of Done?

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Internal references:

Pull Request Review Checklist
Software Engineering Expectations
Technical Design Template
Pull Request Documentation

[github-actions]

	Warnings
⚠️	PR has more than 500 lines of code changing. Consider splitting into smaller PRs if possible.

Generated by 🚫 dangerJS against 556abbc

[aataraxiaa]

Nice one @ayoy! Tested and works great. +1 for tests and documentation!