Add unit tests to ISIS Energy Transfer presenter and data validator

[MohamedAlmaki]

Blocked because parent class of presenter is a Qt object

Describe the outcome that is desired.

The ISIS Energy Transfer Tab has been refactored into the MVP pattern in this PR. Currently, the presenter ISISEnergyTransferPresenter.h and the data validator ISISEnergyTransferDataValidator.h have no unit tests. The goal of this issue is to add unit tests to the presenter and the data validator. Describe any solutions you are considering

The tests could be written using the CxxTest test suite like other unit tests in the project

Acceptance Criteria

• [ ] ISISEnergyTransferPresenter has better unit test coverage
• [ ] ISISEnergyTransferDataValidator has its own unit tests

[MohamedAlmaki]

This is blocked until the refactoring of all tabs is done. I've faced multiple issues when trying to mock QT objects

[robertapplin]

It looks like this might overlap with #36897