Enable nontrapping-fptoint feature while invoking wasm-opt

[godvino]

Without enabling this feature, trying to build a Leptos project in release profile with strip enabled results in errors such as:

[wasm-validator error in function 27] unexpected false: all used features should be allowed, on 
(i32.trunc_sat_f64_u
 (local.get $8)
)
[wasm-validator error in function 27] unexpected false: all used features should be allowed, on 
(i32.trunc_sat_f64_u
 (local.get $9)
)
[wasm-validator error in function 207] unexpected false: all used features should be allowed, on 
(i32.trunc_sat_f64_u
 (local.get $4)
)
Fatal: error validating input

See rust-lang/rust#137322

[gbj]

Looks good to me, thank you!