fix: strip quotes suggestion appearing on any literal search with no results

Created by: attfarhan

Fixes an issue with a previous release blocker's fix https://github.com/sourcegraph/sourcegraph/commit/d4e24b9fe2ccd8f444d9a2339ef42fbd1e0860be. The suggested query would appear on all searches, rather than just those that contain a quote, because we were scanning for a " character in the query that was already processed into a Query object.

Test plan: Manual testing