Select: Fixes issue preserving search term (input) when selecting a value

[torkelo]

Fixes an issue with preserving the search query & filtering after selecting a value, even after doing the correct onInputChange implementation according to the react select docs it did not work as our middleware implementation did not take into account scenarios where we want to preserve the search query after selection and always cleared the "hasInputValue" state which sets filterOption to null which disabled search filtering.

Related to grafana/scenes#709

[grafana-delivery-bot]

Hello @torkelo!
Backport pull requests need to be either:

• Pull requests which address bugs,
• Urgent fixes which need product approval, in order to get merged,
• Docs changes.

Please, if the current pull request addresses a bug fix, label it with the type/bug label.
If it already has the product approval, please add the product-approved label. For docs changes, please add the type/docs label.
If the pull request modifies CI behaviour, please add the type/ci label.
If none of the above applies, please consider removing the backport label and target the next major/minor release.
Thanks!

[grafana-delivery-bot]

This PR must be merged before a backport PR will be created.

[L-M-K-B]

Looks good from my point of view.

[tskarhed]

Small typo, I presume