[ty] Reduce 'complex_constrained_attributes_2' runtime (astral-sh#19001)

Re: astral-sh#18979 (comment)

Each check increases the runtime by a factor of 3, so this should be an
order of magnitude faster.

Author: sharkdp

crates/ruff_benchmark/benches/ty.rs

@@ -428,10 +428,6 @@ fn benchmark_complex_constrained_attributes_2(criterion: &mut Criterion) {
                                 return
                             if isinstance(self.b, str):
                                 return
-                            if isinstance(self.b, str):
-                                return
-                            if isinstance(self.b, str):
-                                return
                     "#,
                 )
             },