Positive coverage: prove_wf / static lifetime

1 test exercised this rule:

Source location: tests/well_formed_trait_ref.rs:71

#[test]
fn static_lifetime_param() {
    FormalityTest::new(crates![crate foo {
        trait Trait1<'a> {}

        struct S1 {}

        impl Trait1<'static> for S1 {}

        struct S2 where S1: Trait1<'static> {}
    }])
    .skip_execute()
    .ok()
}