Add "and"/"or" operator to the Policy conditions

### Current Behavior

At this moment there is no operator selection possible in the policy conditions. It is also not clear if the default is AND or OR. It seems to be an OR.

### Proposed Behavior

It would be good to add a dropdown with the choice of operator. For example you want to have a policy where the EPSS score > x AND severity is Y

### 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 enhancement was already requested