`build_spdx_license_expression` breaks on deprecated licenses

To reproduce:
```
from licensedcode.cache import build_spdx_license_expression
build_spdx_license_expression("broadcom-linking-unmodified")
```

```
Traceback (most recent call last):
File "", line 1, in
File "lib/python3.10/site-packages/licensedcode/cache.py", line 514, in build_spdx_license_expression
return parsed.render(template='{symbol.wrapped.spdx_license_key}')
File "lib/python3.10/site-packages/license_expression/__init__.py", line 1283, in render
return template.format(symbol=self)
AttributeError: 'LicenseSymbol' object has no attribute 'wrapped'
```