Add filename when pinning asset content

[SethDocherty]

Extend the pin method within Assets to add a name to the created pin. This will help when trying to understand what the CID content is when viewing on the local IPFS node.

Reference: https://docs.ipfs.tech/reference/kubo/rpc/#api-v0-pin-add

[matthewnanas]

Addressed in 625b42b

[SethDocherty]

The next thing to work out is how we can pass in the filename when the asset object is created. It's not quite simple since we can't rely on using the value from the pgstac-asset obj, item.id, as a filename since a pgstac-asset obj can have multiple asset files.

We could specify which asset, but that may add more complexity than we want. Anyway, it is not something that needs to be resolved right now.