Migrating Nexus from PyQt to PySide2/6

Every other applications internally developed at PASSCAL are or will be using Pyside2/6 (as per your request). We cannot have both the PyQt and Pyside2/6 libraries installed in a Conda environment at the same time due to conflicting dependencies. Until Nexus is migrated to Pyside2/6, the software group will not be able to add new GUI applications to PASSOFT.