TypeError: Utils.isRegExp is not a function

No matter how I try to run mjolnir, it always seems to fail right away with this error message:

```text
/opt/mjolnir/node_modules/config/lib/config.js:1006
} else if (Utils.isRegExp(parent)) {
^

TypeError: Utils.isRegExp is not a function
at _clone (/opt/mjolnir/node_modules/config/lib/config.js:1006:22)
at Config.cloneDeep (/opt/mjolnir/node_modules/config/lib/config.js:1046:10)
at /opt/mjolnir/node_modules/config/lib/config.js:1318:32
at Array.forEach ()
at util.extendDeep (/opt/mjolnir/node_modules/config/lib/config.js:1293:9)
at /opt/mjolnir/node_modules/config/lib/config.js:651:12
at Array.forEach ()
at util.loadFileConfigs (/opt/mjolnir/node_modules/config/lib/config.js:648:16)
at new Config (/opt/mjolnir/node_modules/config/lib/config.js:113:27)
at Object. (/opt/mjolnir/node_modules/config/lib/config.js:1510:31)

Node.js v23.0.0
```

This is on `v1.8.0` as well as `main`

Invocations I've tried:

- `node lib/index.js --mjolnir-config ./config/production.yaml`
- `/usr/bin/node /opt/mjolnir/lib/index.js --mjolnir-config /opt/mjolnir/config/production.yaml`
- `yarn run start:dev --mjolnir-config /opt/mjolnir/config/production.yaml`

\* This is a **Debian 12** system. I installed nodejs from apt, then `corepack enable` for yarn. I followed the [self-build guide](https://github.com/matrix-org/mjolnir/blob/main/docs/setup_selfbuild.md) and there were no errors until trying to run it.

Start with lib/index.js and the self-build guide, reproducing the startup commands with Node.js v23 on Debian 12. Inspect the reported failure in node_modules/config/lib/config.js and the project's dependency setup; done means the documented startup invocation works without the TypeError or the supported Node.js requirements are clearly established.

Written by the indexing model from the issue text.