Fix whitespace in pretty printed PatKind::Range

[dtolnay]

Follow-up to #92238 fixing one of the FIXMEs.

macro_rules! repro {
    ($pat:pat) => {
        stringify!($pat)
    };
}

fn main() {
    println!("{}", repro!(0..=1));
}

Before: 0 ..=1
After: 0..=1

The canonical spacing applied by rustfmt has no space after the lower expr. Rustc's parser diagnostics also do not put a space there:

rust/compiler/rustc_parse/src/parser/pat.rs

Line 754 in df96fb1

.note("inclusive ranges must be bounded at the end (`..=b` or `a..=b`)")

[rust-highfive]

r? @Mark-Simulacrum

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[Mark-Simulacrum]

@bors r+ rollup

[bors]

📌 Commit bc1a1ff has been approved by Mark-Simulacrum