Contains in Queries does not work with optionals.

[proggeramlug]

I'm passing a String (non-optional) into a query like:

let name: String = "test"
query.filter(\.$name ~~ name)

and I'm getting:

Fatal error: Only string binds are supported with contains.

The fix (not the best probably) for me right now is this:

extension Optional: CustomStringConvertible where Wrapped == String {
    public var description: String {
        return self ?? ""
    }
}

However, I'm wondering why there is an Optional<String> in the function at all, I'm passing a String. https://github.com/vapor/fluent-kit/blob/master/Sources/FluentSQL/SQLQueryConverter.swift#L248