Bug in basic_example.py due to two corner air-gaps

[shobhits72]

Describe the bug
The error occurs when two corner air-gaps are simulated simultaneously (one at air_gap_position = 0 and other at air_gap_position = 100 with air_gap_method = "percent"

To Reproduce
Steps to reproduce the behavior:

1. Go to 'basic_example.py'
2. For any component: set air_gap_method = 'percent' and add two or more air-gaps with the condition that both corner air-gaps are present.
3. The corner air-gaps are positioned as: air_gap_position = 0 and air_gap_position = 100. An example is shown below

5. See error

Screenshots