Error on get_collection_from_opensea(): 404 Client Error: Not Found for url: https://api.opensea.io/api/v1/collection/slug

**Describe the bug**
When calling `get_collection_from_opensea('cool-cats-nft')` an exception `404 Client Error: Not Found for url: https://api.opensea.io/api/v1/collection/cool-cats-nft` is thrown. I am using a proper slug


**Information**

* Collection link/name: any collection
