fix: don't suggest quoted queries in literal mode

Created by: attfarhan

Fixes https://github.com/sourcegraph/sourcegraph/issues/6008.

When queries fail due to "too many repos" or "no repos matching" errors, we would suggest alternative queries which append a repo to the query. However, in literal mode, the match string is wrapped in quotes in regexp-land ensure an exact match, so the suggested queries would return the match string as wrapped in quotes. This fixes it by simply appending patternType:regexp to existing suggestions.

This isn't the ideal solution but there are a lot of places we assume our search is regexp-only, so will need more time to improve this.