LicenseRef-scancode-proprietary-license is added for pypi mako package

### Description

Mako is an MIT-licensed package, but the `LicenseRef-scancode-proprietary-license` licenseref is added for it. It's possible that it's picking up on the word "commercial" in the [README file](https://clearlydefined.io/file/609b6f3a1ef00748e4154adb0037fd77200b1b77ecac2ff910b8ea435891feb2), even though it's saying explicitly that commercial use is allowed.

It seems like just the word "commercial" appearing is a bit too aggressive for assuming a proprietary license.

### How To Reproduce

Shows up in [ClearlyDefined](https://clearlydefined.io/definitions/pypi/pypi/-/mako/1.3.6) using ScanCode 32.3.0.