get rid of transfer samples

# Feature Request

The transfer samples are based on the EDC-DataPlane that will get soon removed from the project ([issue](https://github.com/eclipse-edc/Connector/issues/5838)), plus, the high level samples can now been found in the [Dataspace Hub project](https://github.com/eclipse-dataspace-hub).

Let's remove them

## Which Areas Would Be Affected?

_e.g., DPF, CI, build, transfer, etc._

## Why Is the Feature Desired?

_Are there any requirements?_

## Who will sponsor this feature?

_Please @-mention the committer that will sponsor your feature_.

## Solution Proposal

_If possible, provide a (brief!) solution proposal._

Start by locating the transfer samples in the Samples repository and read issue 5838 to confirm which EDC-DataPlane components are being removed. Remove the obsolete transfer samples while checking the remaining sample references and project build; done means those samples and their references are gone without breaking the rest of the project.

Written by the indexing model from the issue text.