CSS Issues when BASE_PATH is set

### Peering Manager version

v1.9.3

### Python version

3.12

### Steps to Reproduce

1. Configure BASE_PATH in extra.py
2. Launch peering-manager docker container
3. Login as admin


### Expected Behavior

Front page should render correctly and the dark/light mode toggle should work

### Observed Behavior

Peering Manager Logo appears twice and dark/light mode toggle doesn't work