Fix minor min-parsing issues

[jaybosamiya-ms]

Hit some issues when attempting to run verusfmt on https://github.com/secure-foundations/human-eval-verus/blob/main/tasks/human_eval_001.rs ; specifically, our minimal parser would consider the parenthesis in '(' to be syntactically-relevant, rather than ignore it, thereby causing a:

thread 'main' panicked at src/rustfmt.rs:51:10:
Minimal parsing should never fail. If it did, please report this as an error.: Error { variant: ParsingError { positives: [COMMENT, tt], negatives: [] }, location: Pos(5984), line_col: Pos((155, 9)), path: None, line: "        } else if c == ')' {", continued_line: None }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

This PR fixes the issues.

Automatically-minimized example that triggers the issue before this PR:

verus! {

fn a()
    ensures
{
    {
        if '(' {
            if 0 {
            }
        }
    }
}

} // verus!