Make SQLite json/jsonb values json.RawMessage instead of []byte

This in response to code review feedback, it's a little more correct to
make json/jsonb values `json.RawMessage` instead of `[]byte`. The former
is a form of the latter, but better represents that the value is meant
to be JSON.

Author: brandur

internal/codegen/golang/sqlite_type.go

@@ -57,7 +57,7 @@ func sqliteType(req *plugin.GenerateRequest, options *opts.Options, col *plugin.
 		return "sql.NullTime"
 
 	case "json", "jsonb":
-		return "[]byte"
+		return "json.RawMessage"
 
 	case "any":
 		return "interface{}"