nginx - "listen ... http2" directive is deprecated

### Steps To Reproduce

1. Deploy a self-hosted instance via Docker following recommend steps.
2. Open logs/nginx/error.log from the bwdata folder.

### Expected Result

No line is present in the logs indicating that the nginx configuration is relying on the deprecated "listen ... http2" directive.

### Actual Result

From the error.log on my deployment:
```
2026/02/04 16:53:21 [warn] 1#1: the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/conf.d/default.conf:17
2026/02/04 16:53:21 [warn] 1#1: the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/conf.d/default.conf:18
```

### Screenshots or Videos

_No response_

### Additional Context

_No response_

### Build Version

2026.1.0

### Environment

Self-Hosted

### Environment Details

_No response_

### Issue Tracking Info

- [x] I understand that work is tracked outside of Github. A PR will be linked to this issue should one be opened to address it, but Bitwarden doesn't use fields like "assigned", "milestone", or "project" to track progress.