Compare overtime checked and displayed revisions

[Carla-Moz]

This PR fulfills the requirements of Handle checked and displayed selected revisions. This is the last remaining part of the Compare over time component. The hash to hide it is removed. The "Compare" button will remain disabled (see this commit) until the next PR to add react-router config to fetch the data.

New File Created: In this commit, I created a new file called useSearchResults because both the Revisions component in "With base" and "Overtime" handle the search results toggle the same way, including showing the error when the user attempts to select more than 3 revisions. This required updating the CompareWithBase file.

Style Tweaks: In this commit, I did a small update on styles/SearchContainerStylesand styles/Documents to better reflect the overflow of the search results dropdown.

Update test coverage in CompareOvertTime.test: please check this commit.

Side note: I talked to Dasha about toggling the display of the "Compare with Base" and "Compare Over time" component in which clicking on one hides the content below their respective headers so they function like radio buttons. This is not handled in this PR but something I think would be helpful to do in a future PR.

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 97.88%. Comparing base (7e0f0bc) to head (936c88e).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## beta #640 +/- ## ========================================== + Coverage 97.76% 97.88% +0.11% ========================================== Files 66 66 Lines 1387 1417 +30 Branches 235 241 +6 ========================================== + Hits 1356 1387 +31 + Misses 29 28 -1 Partials 2 2 ```

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[julienw]

Side note: I talked to Dasha about toggling the display of the "Compare with Base" and "Compare Over time" component in which clicking on one hides the content below their respective headers so they function like radio buttons. This is not handled in this PR but something I think would be helpful to do in a future PR.

Yeah I don't like the current situation much either, happy to improve it in any way.