bug: `just lint` / `harper-cli` crash on markdown hex test file - debug build only

[hippietrail]

Describe the bug
just lint crashes on a .md file I created to test a hexadecimal number lexer on.

To Reproduce
Steps to reproduce the behavior:

1. Download the markdown file hex.md linked below.
2. Go to the terminal
3. Enter just lint <path to hex.md>
4. See error
5. run with RUST_BACKTRACE=1 environment variable to display a backtrace

hex.md

On delving further, in a new clone of the repo, I discovered building and running as release from cargo works fine:
cargo run --release --bin harper-cli lint ~/harper-test/hex.md

But regular builds from cargo crash just as with just lint
cargo run --bin harper-cli lint ~/harper-test/hex.md

Expected behavior
Perhaps linting errors for each hex number.

Platform
Running from the Mac commandline

Additional context
Backtrace:

% just lint ../harper-test/hex.md
cargo run --bin harper-cli -- lint ../harper-test/hex.md
warning: /Users/hippietrail/harper/harper-wasm/Cargo.toml: unused manifest key: package.private
warning: /Users/hippietrail/harper/harper-cli/Cargo.toml: unused manifest key: package.private
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.30s
     Running `target/debug/harper-cli lint ../harper-test/hex.md`
thread 'main' panicked at harper-core/src/span.rs:100:9:
attempt to subtract with overflow
stack backtrace:
   0: rust_begin_unwind
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/std/src/panicking.rs:665:5
   1: core::panicking::panic_fmt
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/panicking.rs:76:14
   2: core::panicking::panic_const::panic_const_sub_overflow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/panicking.rs:182:21
   3: harper_core::span::Span::pulled_by
             at ./harper-core/src/span.rs:100:9
   4: <harper_core::linting::correct_number_suffix::CorrectNumberSuffix as harper_core::linting::Linter>::lint
             at ./harper-core/src/linting/correct_number_suffix.rs:14:31
   5: <harper_core::linting::lint_group::LintGroup<T> as harper_core::linting::Linter>::lint
             at ./harper-core/src/linting/lint_group.rs:136:47
   6: harper_cli::main
             at ./harper-cli/src/main.rs:61:29
   7: core::ops::function::FnOnce::call_once
             at /Users/hippietrail/.rustup/toolchains/stable-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
error: Recipe `lint` failed on line 244 with exit code 101

[elijah-potter]

This has been fixed as part of #529 already. Just take a look at harper-core/src/span.rs:100:9: on that branch.