extra-file is not updated by release-please

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Please provide the following details.

#### Environment details

- OS: github workflow on ubuntu-latest
- `release-please` version: googleapis/release-please-action@v4

#### Steps to reproduce

1. Setting up new rust project
2. bootstrap it with release-please
3. adding extra file sw.js in public folder with content: const CACHE_VERSION = "0.0.0"; // x-release-please-version
4. release-please-config.json:

```json
{
"packages": {
".": {
"changelog-path": "CHANGELOG.md",
"release-type": "rust",
"bump-minor-pre-major": false,
"bump-patch-for-minor-pre-major": false,
"draft": false,
"prerelease": false,
"extra-files": [
{
"type": "generic",
"path": "public/sw.js"
}
]
}
},
"$schema": "https://raw.githubusercontent.com/googleapis/release-please/main/schemas/config.json"
}
```

5. setting up github workflow with content:

```yaml
name: release-please

description: |
Functional workflow for release-please. Automatically creates a release PR with version bump,
changelog, and Git tag based on conventional commits.

on:
push:
branches:
main

jobs:
release:
name: Create release PR (release-please)
runs-on: ubuntu-latest
steps:
- uses: googleapis/release-please-action@v4
with:
token: ${{ secrets.GITHUB_TOKEN }}
release-type: rust
target-branch: main
config-file: release-please-config.json
manifest-file: .release-please-manifest.json
```

6. push it with "fix: test the bug" to github
7. result: sw.js is not updated.

Making sure to follow these steps will guarantee the quickest resolution possible.

Thanks!