[pypi] spdxcorrect is too aggressive for declaredLicense

at https://github.com/clearlydefined/crawler/blob/master/providers/fetch/pypiFetch.js#L77

```js
_extractDeclaredLicense(registryData) {
const classifiers = get(registryData, 'info.classifiers')
if (!classifiers) return null
for (const classifier in classifiers) {
if (classifiers[classifier].includes('License :: OSI Approved ::')) {
const lastColon = classifiers[classifier].lastIndexOf(':')
const rawLicense = classifiers[classifier].slice(lastColon + 1)
return spdxCorrect(rawLicense)
}
}
return null
}
```

For example https://pypi.org/pypi/Flask/json

looks at info.classifiers and pulls out

```
"License :: OSI Approved :: BSD License",
```

runs spdx-correct on `BSD License` => `BSD-2-Clause`
when it should be `BSD-3-Clause`

We should probably drop this from the crawler side entirely and let the summarizers parse the data without spdx correct