Dual-license "X or Y" statement detected as AND instead of OR

### Description

Dual-license statement "X or Y" is detected as X AND Y instead of X OR Y.
https://github.com/g-truc/glm/blob/master/copying.txt contains:
`GLM is licensed under The Happy Bunny License or MIT License`
followed by both full license texts. ScanCode outputs:
`"detected_license_expression_spdx": "LicenseRef-scancode-happy-bunny AND MIT"`

Expected: `LicenseRef-scancode-happy-bunny OR MIT`

### How To Reproduce

```
curl -s "https://raw.githubusercontent.com/g-truc/glm/master/copying.txt" -o copying.txt
scancode --license --json-pp result.json copying.txt
cat result.json | grep detected_license_expression_spdx
```

### System configuration

* OS: macOS
* ScanCode version: 32.5.0
* Installation: pip