Frontend fails because it tries to rewrite readonly ngnix default.conf

### Current Behavior

We customize our default.conf file for ssl termination and various other reasons. 4.9.1 should not attempt to rewrite the file. Our configuration is controlled by puppet and we don't want the container making changes.

### Steps to Reproduce

1. docker-compose.yml contains
```
volumes:
- /opt/nginx/conf.d/:/etc/nginx/conf.d/
```
2. docker pull newest dtrack-frontend
3. docker-compose up
4. 502 Bad gateway to frontend

```
dtrack-frontend_1 | /docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
dtrack-frontend_1 | sed: can't create temp file '/etc/nginx/conf.d/default.confXXXXXX': Permission denied
opt_dtrack-frontend_1 exited with code 1
```

### Expected Behavior

Don't try to rewrite our default.conf

> Do not check whether the default configuration file has been changed vs
what is packaged with the distribution's installation. We customized the
file and want the changes the applied regardless.

No I don't, please restore this check or fail on the rewrite more gracefully
https://github.com/nginxinc/docker-nginx-unprivileged/blob/1.25.2/entrypoint/10-listen-on-ipv6-by-default.sh
was wise to allow users to control this.

### Dependency-Track Frontend Version

4.9.1

### Browser

Google Chrome

### Browser Version

_No response_

### Operating System

Linux

### Checklist

- [X] I have read and understand the [contributing guidelines](https://github.com/DependencyTrack/dependency-track/blob/master/CONTRIBUTING.md#filing-issues)
- [X] I have checked the [existing issues](https://github.com/DependencyTrack/frontend/issues) for whether this defect was already reported