Ignore confusable_idents warning in test

    error: found both `σ` and `o` as identifiers, which look alike
       --> test_suite/tests/test_gen.rs:734:13
        |
    292 |         σ: f64,
        |         - other identifier used here
    ...
    734 |             o: T,
        |             ^ this identifier can be confused with `σ`
        |
    note: the lint level is defined here
       --> test_suite/tests/test_gen.rs:5:9
        |
    5   | #![deny(warnings)]
        |         ^^^^^^^^
        = note: `#[deny(confusable_idents)]` implied by `#[deny(warnings)]`

test_suite/tests/test_gen.rs

@@ -4,6 +4,7 @@
 
 #![deny(warnings)]
 #![allow(
+ confusable_idents,
  unknown_lints,
  mixed_script_confusables,
  clippy::derive_partial_eq_without_eq,