Remove Dependabot PRs from release notes?

Dependabot recently started barraging my project with PRs, and while useful, it's making release notes quite noisy. I can't seem to figure out how to remove dependabot PRs though.

```
{
"plugins": [
[
"npm",
{
"monorepoChangelog": false
}
],
[
"omit-release-notes",
{
"username": "dependabot[bot]"
}
],
"first-time-contributor",
"released"
],
…
}
```

Using `omit-release-notes` seems like it should work but it doesn't. Is there something I'm missing about how this works?