fix telescope button import for case sensitive OS

[fpreiss]

The electron app won't build on case sensitive operating systems without this fix.

During npm run package on linux:

[0] npm run build:main exited with code 0
[1] ERROR in ./src/renderer/components/TelescopeButton.tsx 3:0-25
[1] Module not found: Error: Can't resolve './telescope.css' in '/home/fpreiss/Downloads/github/llama-fs/electron-react-app/src/renderer/components'