Fixes double 'String' on string & UUID type

Created by: taufik-rama

Continuation from #10569, I just fixed the remaining place where it's needed (Edit: it seems that that changes got reverted. I double-checked & had to do more-or-less the same changes)

I've tested this changes by building the Dockerfile & regenerating my projects, it worked fine

Before

/// struct for passing parameters to the method [`users_delete`]
#[derive(Clone, Debug, Default)]
pub struct UsersDeleteParams {
    pub id: Option<StringString>,
    // ...
}

After

/// struct for passing parameters to the method [`users_delete`]
#[derive(Clone, Debug, Default)]
pub struct UsersDeleteParams {
    pub id: Option<String>,
}

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