Use new Temporary Settings for fuzzy file finder
Created by: olafurpg
Feature request description
Currently, the fuzzy file finder uses localStorage to save the last fuzzy query per-repository.
https://github.com/sourcegraph/sourcegraph/blob/896386b7dd5a2e6fdcb5b87df3aed09df95fdf74/client/web/src/components/fuzzyFinder/FuzzyModal.tsx#L67
We should use the new Temporary Settings instead so that these queries are synchronized between sessions in different browsers https://docs.sourcegraph.com/dev/background-information/web/temporary_settings