Importing RTB changes the plot style for all matplotlib plots

[vonHartz]

Describe the bug
Importing RTB changes the plot style for all matplotlib plots - even those not using RTB.

Version information
PyPI: roboticstoolbox-python==1.1.1

To Reproduce
Steps to reproduce the behavior:

import matplotlib.pyplot as plt
plt.imshow([[0,1],[0,1]])
plt.show()
import roboticstoolbox as rtb
plt.imshow([[0,1],[0,1]])
plt.show()

Expected behavior
The plot style should be consistent regardless of RTB, but the second plot has a grid.
For example, plots also get gray backgrounds.

Screenshots
Before and after import

Environment (please complete the following information):

• Linux
• Python 3.10