Suppress rust warnings from outputted `prisma.rs`

[dukeeagle]

Awesome work here! Would it be possible to prevent add an #![allow(warnings)] to the top of prisma.rs in order to avoid unnecessary rust compiler warnings such as:

warning: function `equals` is never used
    --> src/prisma.rs:5438:16
     |
5438 |         pub fn equals(value: i32) -> WhereParam {
     |                ^^^^^^

[Brendonovich]

This used to be done but was removed because of #306. The docs now recommend to do this: