extend while_let_loop to loop { let else }

[bend-n]

now lints on

let mut x = [1,2,3].into_iter();
loop {
   let Some(x) = x.next() else { break };
   dbg!(x);
}

changelog: [`while_let_loop`]: extend to lint on `let else`

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[samueltardieu]

This should be auto-fixable, right?

[bend-n]

in theory, yeah?

[dswij]

Should be auto-fixable. Let's do it in a separate PR. I created an issue for this #15702.

@bend-n would you want to help with this?