fix overly strict lifetime bound in Default impl

[asmello]

This one is a bit subtle. It causes some code relying on the Default trait implementation to be rejected by the compiler:

fn or_default(ptr: &Pointer) -> &Pointer {
    Some(ptr).unwrap_or_default()
}

This is because this desugars to:

match self {
    Some(x) => x, // '_
    None => Self::default() // 'static
}

Which demands that '_ == 'static to be accepted. This is overly strict, we should coerce to whatever lifetime the original & had instead.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.8%. Comparing base (f3c23b9) to head (e0d7a70).

Additional details and impacted files

Files with missing lines	Coverage Δ
src/pointer.rs	95.6% <100.0%> (+<0.1%)	⬆️

[chanced]

Wow, great catch!