Uploaded SBOM or VEX silently ignored if the first line is empty

### Current Behavior

It seems that if I upload a BOM json document with first line being empty the contents are ignored.

### Steps to Reproduce

1. Create a new project
2. Upload [bom.json](https://github.com/user-attachments/files/20394204/bom.json)
3. Observe that no components are added

### Expected Behavior

The contents are not ignored.

Ignoring the contents silently instead of returning an error makes this issue much worse. It's rather difficult to understand what happened if you don't know.

### Dependency-Track Version

4.13.1

### Dependency-Track Distribution

Container Image

### Database Server

PostgreSQL

### Database Server Version

_No response_

### Browser

N/A

### 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/dependency-track/issues) for whether this defect was already reported