remove unused internal/iut/server package from etos-api

### Description

The package is no longer used. The code should be removed.

### Additional Context

_No response_

### Logs

_No response_

### Expected Behavior

The package shouldn't be there.

### Steps To Reproduce

_No response_

### The version of this project/repo, if applicable

main

### The version/edition of the Eiffel Protocol used, if applicable

main