SQL query with sql funcs can generate duplicate fields

[matt2e]

Not sure if this is a sqlc bug or an FTL one.
Steps:

• ftl dev examples/go/mysql
• Add this to that module's queries.sql file:

-- name: CreateConcatRequest :exec
INSERT INTO requests (data) VALUES (CONCAT(LOWER(?), LOWER(?)));

This generates this invalid struct with duplicate fields:

type CreateConcatRequestQuery struct {
  	Lower string
  	Lower string
}

Workaround: use named args

-- name: CreateConcatRequest :exec
INSERT INTO requests (data) VALUES (CONCAT(LOWER(sqlc.arg(part1)), LOWER(sqlc.arg(part2))));