Uncaught SyntaxError: invalid escape sequence in regular expression

While experimenting with a solution that uses `javy`, I happened to include the [`camelcase`](https://www.npmjs.com/package/camelcase) package. When attempting to build, I get the error below.

```
thread '' panicked at 'called `Result::unwrap()` on an `Err` value: Uncaught SyntaxError: invalid escape sequence in regular expression
at RegExp (native)
at (:10)
at ./node_modules/camelcase/index.js (script.js:39)
at __webpack_require__ (script.js:63)
at (:2)
at ./src/index.js (script.js:29)
at __webpack_require__ (script.js:63)
at (script.js:115)
at (script.js:118)
at webpackUniversalModuleDefinition (script.js:15)
at (script.js:120)
', crates/core/src/lib.rs:35:61
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: the `wizer.initialize` function trapped

Caused by:
wasm trap: wasm `unreachable` instruction executed
wasm backtrace:
0: 0xcb9d9 - !__rust_start_panic
note: using the `WASMTIME_BACKTRACE_DETAILS=1` environment variable to may show more debugging information

Error: Couldn't create wasm from input
```

[Reproduction here](https://github.com/nickwesselman/javy-camelcase-issue/blob/main/src/index.js), I was able to isolate the issue to the following lines in `camelcase`:

```
const IDENTIFIER = /([\p{Alpha}\p{N}_]|$)/u;
const SEPARATORS = /[_.\- ]+/;
const LEADING_SEPARATORS = new RegExp('^' + SEPARATORS.source);

// THIS LINE APPEARS TO BE THE ISSUE
const SEPARATORS_AND_IDENTIFIER = new RegExp(SEPARATORS.source + IDENTIFIER.source, 'gu');
```

Not sure what the exact issue is, or how common it might be in other code.