Made typos in docs searches return some results.

[sarahboyce]

When looking into #1347, there is a suggestion that we should show search results for "databasess" instead of a 404. However, this currently returns no results: https://docs.djangoproject.com/en/5.1/search/?q=databasess

Our search isn't very forgiving for spelling errors (not a "fuzzy" search).
As a suggestion, I think we can return some results that have a ranking instead of returning no results.

Fixes #1932

[pauloxnet]

I tried to use Trigram for handling misspelling cases, but it was on the long list of things to improve, so thanks for working on that.

[pauloxnet]

I had to test it locally to make sure I was proposing a solution that was as efficient as before. :)

I noticed that we were annotating the search rank without needing to show it, so I used "alias" and proposed the minimum number of code changes to have the suggested results in the list.

The SQL code generated with the suggested changes is slightly different but equally efficient and no longer produces the rank in output since it was not shown.

I restored the unmodified code with the previous formatting to make it easier to consult the Git history.

[pauloxnet]

Sorry @sarahboyce if I'm replying only now.

Thanks for continuing this PR, I tried to think better about the goal we want to achieve, and I opened the issue #1932

The goal I had in mind was to improve the current query, which I had created in the past, trying to maintain efficiency.

[pauloxnet]

Thanks again for so many updates in your PR.