Refactor Select documentation to no longer mention SelectNext

[acelaya]

This PR follows-up on https://github.com/hypothesis/frontend-shared/pull/1619

This PR replaces the /input-select-next documentation page with /input-select, which has very similar content and examples, but always using Select and MultiSelect and no longer mentioning SelectNext.

Additionally, it deprecates SelectNext, and recommends using one of the other two components as drop-in replacements.

Technically speaking, two breaking changes are introduced here:

• The /input-select-next URL will no longer work. I guess we could potentially make it redirect to /input-select if we think this is a big problem.
• The Option component's displayName has changed from 'SelectNext.Option' to 'Select.Option', which could make some test break, but I already have branches almost ready to transition away from SelectNext anyway, so it shouldn't be a big problem.
  • EDIT: I can confirm no tests break here, because we were finding options via Select.Option function reference, rather than via its display name.

[codecov[bot]]

Codecov Report

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

Project coverage is 99.90%. Comparing base (73dfdf2) to head (acf7bea).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1620 +/- ## =========================================== - Coverage 100.00% 99.90% -0.10% =========================================== Files 62 62 Lines 1071 1071 Branches 410 410 =========================================== - Hits 1071 1070 -1 - Misses 0 1 +1 ```

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[acelaya]

Codecov is reporting a drop in code coverage, but I think it's a false positive. Locally, it reports a coverage of 100%, and if you go to codecov's report, there's no line highlighted as uncovered.