Needless exponent in excessive_precision suggestion

[dtolnay]

fn main() {
    let _ = 1.000_000_000_000_001e-324_f64;
}

warning: float has excessive precision
 --> src/main.rs:2:13
  |
2 |     let _ = 1.000_000_000_000_001e-324_f64;
  |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider changing the type or truncating it to: `0e0_f64`
  |
  = note: `#[warn(clippy::excessive_precision)]` on by default
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#excessive_precision

Clippy suggests 0e0_f64, but this quantity is more conventionally written as 0_f64 or 0.0_f64. I'm guessing clippy is simplistically doing "if there is e in the original, then use e in the suggestion" but this isn't great for the underflow case.

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Rust version (rustc -Vv):

rustc 1.57.0-nightly (aa7aca3b9 2021-09-30)
binary: rustc
commit-hash: aa7aca3b954131720df725e70d12e902eb3be1de
commit-date: 2021-09-30
host: x86_64-unknown-linux-gnu
release: 1.57.0-nightly
LLVM version: 13.0.0

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