NullPointerException when searching for components without filter

### Current Behavior:
This is a bug of category "not so nice". There is no impact on functionality.
When you perform a search for components, a warning is written to the logs.

### Steps to Reproduce:
1. Navigate to "Components"
2. Do not enter anything - Click "Search"

The log shows 2 warnings:
```
WARN unhandled due to prior sendError
WARN /api/v1/component/identity
```

The stack trace attached to the logs shows:
```
java.lang.NullPointerException: null
at org.dependencytrack.persistence.QueryManager.getComponents(QueryManager.java:759)`
at org.dependencytrack.resources.v1.ComponentResource.getComponentByIdentity(ComponentResource.java:153)
```

### Expected Behavior:
The case where a user enters no filter criteria should be handled more gracefully by Dependency Track, without issuing a warning.

### Environment:

- Dependency-Track Version: 4.2
- Distribution: Docker
- BOM Format & Version: n/a
- Database Server: PostgreSQL
- Browser: Chrome

### Additional Details:
The method QueryManager::getComponents handles many cases of filters, being entered by the users, but not the empty-filters case.