special-casing `'static` when winnowing trivial candidates

The following code compiles (adapted from tests/ui/trivial-bounds/trivial-bounds-object.rs):

// check-pass
trait A { fn test(&self); }

fn foo(x: &dyn A)
where
    dyn A + 'static: A, // Using this bound would lead to a lifetime error.
{
    x.test();
}

while this doesn't:

trait A { fn test(&self); }

fn foo<'s>(x: &dyn A)
where
    dyn A + 's: A, // Using this bound would lead to a lifetime error.
{
    x.test();
    //~^ ERROR explicit lifetime required in the type of `x`
}

There are two candidates to satisfy the bound dyn A + '?0: A:
for the first case:

1. ObjectCandidate(_); no region constraints
2. ParamCandidate(dyn A + 'static: A); requires '?0 = 'static

for the seecond one:

1. ObjectCandidate(_); no region constraints
2. ParamCandidate(dyn A + 's: A); requires '?0 = 's

The different behavior arises because the param candidate in the first case is considered "global", unlike second case. Global param candidates are dropped in favor of any other candidate. This behavior was introduced by #51042 here:
https://github.com/rust-lang/rust/blob/604f185fae9a4b0edf7e28f616a0f53880f8f074/compiler/rustc_trait_selection/src/traits/select/mod.rs#L1816

Start with tests/ui/trivial-bounds/trivial-bounds-object.rs and reproduce the two examples to compare candidate selection. Then read compiler/rustc_trait_selection/src/traits/select/mod.rs around the referenced line and trace how global parameter candidates are winnowed. Done means the lifetime behavior is corrected for the reported cases with appropriate UI test coverage.