Lint on overly-complex lifetime annotations when lifetime subtyping would handle it

A common mistake for beginners writing lifetime annotations is to write something like this:

pub fn min<'a: 'c, 'b: 'c, 'c, T: Ord>(a: &'a T, b: &'b T) -> &'c T {
    if b < a { b } else { a }
}

which while it's not wrong, is rather more complex than necessary.

It would be nice for the compiler to use its own knowledge of subtyping to suggest that the signature change to

pub fn min<'c, T: Ord>(a: &'c T, b: &'c T) -> &'c T {
    if b < a { b } else { a }
}

since that's equivalent.

No file, test, or compiler entry point is named. Use the two min signatures as the acceptance example while locating the relevant lifetime-subtyping diagnostic path; done means the more complex annotation produces a clear suggestion to use the equivalent shared lifetime.