TypeError: unsupported operand type(s) for &: 'int' and 'KeyboardModifier' when running multiple tests on python 3.11 or 3.8 not using the EDM environment when running python chaco/examples/demo/multiaxis_using_Plot.py

**Problem Description**
When running multiple demos using python 3.11 or 3.8 (without EDM), a TypeError: unsupported operand type(s) for &: 'int' and 'KeyboardModifier' will occur after closing the plot window

**Reproduction Steps:**
python chaco/examples/demo/multiaxis_using_Plot.py

**Expected behavior:**
Plot a multiple axis plot without error.

**OS, Python version:**
[MacOS, python 3.11 or python 3.8 (without EDM, the example will pass on EDM)]