Not passing config: "invalid type: null, expected struct SerdeParseConfig"

Currently, it seems like it's not passing config, which makes it throw.

You can see issue with `npm test`

```
console.error
panicked at 'called `Result::unwrap()` on an `Err` value: Error("invalid type: null, expected struct SerdeParseConfig", line: 1, column: 4)', src/lib.rs:12:59

Stack:

Error:
at imports.wbg.__wbg_new_693216e109162396 (/Users/konsumer/Documents/work/rawproto-wasm/target/web/rawproto.js:195:19)
at console_error_panic_hook::hook::h51ddedfd14848316 (wasm://wasm/001da41e:1:323074)
at core::ops::function::Fn::call::hf3855f3e0c0b4e53 (wasm://wasm/001da41e:1:383366)
at std::panicking::rust_panic_with_hook::h47a0e203360b6c10 (wasm://wasm/001da41e:1:361815)
at std::panicking::begin_panic_handler::{{closure}}::h888144d5e9a03cec (wasm://wasm/001da41e:1:371034)
at std::sys_common::backtrace::__rust_end_short_backtrace::h81961607fd97e28e (wasm://wasm/001da41e:1:382298)
at rust_begin_unwind (wasm://wasm/001da41e:1:379472)
at core::panicking::panic_fmt::h4ca53049f45e3264 (wasm://wasm/001da41e:1:380386)
at core::result::unwrap_failed::h6d050dbd00b66340 (wasm://wasm/001da41e:1:371992)
at parse_raw (wasm://wasm/001da41e:1:127376)
```

I `console.log` `cfg` input on `parseRaw`:

```
CONFIG { no_fixed64: false, no_fixed32: false }
```

Start by running npm test and inspect parseRaw in src/lib.rs, especially the line reported in the panic. Compare the CONFIG value logged at the entry point with the value deserialized as SerdeParseConfig. Done means npm test no longer reports a null-config deserialization panic.

Written by the indexing model from the issue text.