cls command fails on Linux - should use IPython %clear magic

[daym]

In src/mslice/widgets/ipythonconsole/ipython_widget.py, the cleanup() method executes cls (?) in ipython to clear the console:

  def cleanup(self):
      if in_mantid():
          self.execute("cls")
          self.execute("import mslice.cli as mc")

This causes a NameError because IPython tries to evaluate it as Python code (variable reference to variable cls):

NameError                                 Traceback (most recent call last)
  Cell In[2], line 1
  ----> 1 cls

Why not just use self.clear() ?

Environment:

• mslice version: 2.13
• OS: Linux
• File: src/mslice/widgets/ipythonconsole/ipython_widget.py

To reproduce:

1. Open mantid
2. Open mslice
3. Close mslice
4. Open mslice
5. See error message