[SRU] veusz fails to start under Python 3.10

[ Impact ]

Veusz fails to start under jammy and kinetic.

[ Test Plan ]

* sudo apt install veusz
* veusz
* Observe that veusz fails to start, with the error indicated in the original description
* Enable proposed (https://wiki.ubuntu.com/Testing/EnableProposed)
* sudo apt install -t kinetic-proposed veusz
  - substitute jammy if testing there
* veusz
* Observe that veusz now starts (try running through the tutorial for a basic functionality test)

[ Regression Potential ]

Pretty low: there are no reverse dependencies for veusz, and the current state is that the application doesn't even start, so there's not much further it can regress.

[ Original Description ]

Attempting to start Veusz on my jammy installation fails. The following is produced as console output:

Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
Traceback (most recent call last):
  File "/usr/bin/veusz", line 33, in <module>
    sys.exit(load_entry_point('veusz==3.3.1', 'gui_scripts', 'veusz')())
  File "/usr/lib/python3/dist-packages/veusz/veusz_main.py", line 369, in run
    app.startup()
  File "/usr/lib/python3/dist-packages/veusz/veusz_main.py", line 267, in startup
    self.splash = makeSplash(self)
  File "/usr/lib/python3/dist-packages/veusz/veusz_main.py", line 69, in makeSplash
    font.setPointSize(font.pointSize()*1.5)
TypeError: setPointSize(self, int): argument 1 has unexpected type 'float'

It would appear that the relevant upstream bug (already fixed) is https://github.com/veusz/veusz/issues/563.